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+% !arara: pdflatex
+% !arara: biber
+% arara: pdflatex: { action: nonstopmode }
+% arara: pdflatex: { action: nonstopmode }
+% --------------------------------------------------------------------------
+% the CHEMMACROS package
+%
+% comprehensive support for typesetting chemistry documents
+%
+% --------------------------------------------------------------------------
+% Clemens Niederberger
+% --------------------------------------------------------------------------
+% https://github.com/cgnieder/chemmacros/
+% contact@mychemistry.eu
+% --------------------------------------------------------------------------
+% If you have any ideas, questions, suggestions or bugs to report, please
+% feel free to contact me.
+% --------------------------------------------------------------------------
+% Copyright 2011-2017 Clemens Niederberger
+%
+% This work may be distributed and/or modified under the
+% conditions of the LaTeX Project Public License, either version 1.3
+% of this license or (at your option) any later version.
+% The latest version of this license is in
+% http://www.latex-project.org/lppl.txt
+% and version 1.3 or later is part of all distributions of LaTeX
+% version 2005/12/01 or later.
+%
+% This work has the LPPL maintenance status `maintained'.
+%
+% The Current Maintainer of this work is Clemens Niederberger.
+% --------------------------------------------------------------------------
+\documentclass[load-preamble+]{cnltx-doc}
+\usepackage[utf8]{inputenc}
+\usepackage[compatibility=newest]{chemmacros}
+\setcnltx{
+ package = {chemmacros},
+ info = {comprehensive support for typesetting chemistry documents},
+ url = https://github.com/cgnieder/chemmacros ,
+ authors = Clemens Niederberger ,
+ email = contact@mychemistry.eu ,
+ abstract = {%
+ \centering
+ \includegraphics{chemmacros-logo.pdf}
+ \par
+ } ,
+ quote-format = \small\biolinumLF ,
+ add-cmds = {
+ abinitio, activatechemgreekmapping, AddRxnDesc, anti, aq, aqi,
+ ba, bond, bridge,
+ cd, ch, changechemgreeksymbol, charrow, chcpd, chemabove, chemalpha,
+ chembeta, ChemCleverefSupport, chemdelta, chemDelta,
+ ChemFancyrefSupport, chemformula@bondlength, chemgamma, ChemModule,
+ chemomega, chemphi, chemPhi, chemsetup, chlewis, chname , cip, cis, ch,
+ CNMR,
+ data, DeclareChemArrow, DeclareChemBond, DeclareChemBondAlias,
+ DeclareChemCharge, DeclareChemEqConstant, declarechemgreekmapping,
+ DeclareChemIUPAC, DeclareChemIUPACShorthand, DeclareChemLatin,
+ DeclareChemNMR, DeclareChemNucleophile, DeclareChemPartialCharge,
+ DeclareChemParticle, DeclareChemPhase, DeclareChemReaction,
+ DeclareChemState,
+ delm, delp, Delta, dexter, Dfi,
+ el, ElPot, endo, entgegen, Enthalpy, enthalpy, entropy,
+ fdelm, fdelp, fmch, fminus, fpch, fplus, fscrm, fscrp,
+ gas, ghs, ghslistall, ghspic, gibbs, gram,
+ hapto, HNMR, Helmholtz, hydrogen,
+ IfChemCompatibilityF, IfChemCompatibilityT, IfChemCompatibilityTF, insitu,
+ invacuo, isotope, iupac,
+ Ka, Kb, Kw,
+ laevus, Lfi, listofreactions, lqd,
+ makepolymerdelims, mch, mega, meta, mhName,
+ NewChemArrow, NewChemBond, NewChemBondAlias,
+ NewChemCharge, NewChemEqConstant, newchemgreekmapping, NewChemIUPAC,
+ NewChemIUPACShorthand, NewChemLatin, NewChemMacroset, NewChemNMR,
+ NewChemNucleophile, NewChemPartialCharge, NewChemParticle, NewChemPhase,
+ NewChemReaction, NewChemState,
+ newman, nitrogen, NMR, Nu, Nuc,
+ orbital, ortho, ox, OX, oxygen,
+ para, pch, per, pH, phase, phosphorus, photon, pKa, pKb, pOH, pos,
+ positron, Pot, ProvideChemArrow, ProvideChemBond, ProvideChemCharge,
+ ProvideChemEqConstant, ProvideChemIUPAC, ProvideChemIUPACShorthand,
+ ProvideChemLatin, ProvideChemNMR, ProvideChemNucleophile,
+ ProvideChemPartialCharge, ProvideChemParticle, ProvideChemPhase,
+ ProvideChemReaction,
+ ProvideChemState, prt,
+ Rad, redox, RemoveChemIUPACShorthand, RenewChemArrow, RenewChemBond,
+ RenewChemCharge, RenewChemEqConstant, renewchemgreekmapping,
+ RenewChemIUPAC, RenewChemIUPACShorthand, RenewChemLatin, RenewChemNMR,
+ RenewChemNucleophile, RenewChemPartialCharge, RenewChemParticle,
+ RenewChemPhase, RenewChemState,
+ Sf, scrm, scrp, second, selectchemgreekmapping, setchemformula,
+ ShowChemArrow, ShowChemBond, sld, Sod, state, sulfur,
+ trans,
+ usechemmodule,
+ val,
+ zusammen
+ } ,
+ add-silent-cmds = {
+ addplot,
+ bottomrule,
+ cancel, cdot, ce, cee, celsius, centering, chemfig, chemname, clap,
+ cnsetup, code, color, cstack, cstsetup,
+ DeclareInstance, DeclareSIUnit, definecolor, draw,
+ electronvolt, endtikzpicture,
+ footnotesize,
+ glqq, grqq,
+ hertz, hspace,
+ includegraphics, intertext, IUPAC,
+ joule,
+ kelvin, kilo,
+ latin, lc, lewis, Lewis, liquid, ltn,
+ metre, midrule, milli, mmHg, mole,
+ nano, nicefrac, num, numrange,
+ ominus, oplus,
+ percent, pgfarrowsdeclarealias, pgfarrowsrenewalias,
+ renewtagform, rightarrow,
+ sample, scriptscriptstyle, setatomsep, setbondoffset, sfrac, shade,
+ shadedraw, shorthandoff, si, SI, sisetup, square, subsection,
+ textcolor, textendash, textsuperscript, tikz, tikzpicture, tiny, toprule,
+ upbeta, upeta, upgamma, usetikzlibrary,
+ volt, vphantom, vspave,
+ xspace,
+ z@, z@skip
+ } ,
+ index-setup = { othercode = \footnotesize , level = \section } ,
+ makeindex-setup = { columns = 2 , columnsep = 1em }
+}
+
+\usepackage{booktabs,array,longtable}
+
+\usepackage{chemfig,cancel,varioref,csquotes}
+
+\usepackage[
+ a4paper,
+ top = .1\paperheight,
+ bottom = .1\paperheight,
+ left = .2\paperwidth,
+ right = .1\paperwidth
+]{geometry}
+
+
+\expandafter\def\csname libertine@figurestyle\endcsname{LF}
+\usepackage[libertine]{newtxmath}
+\expandafter\def\csname libertine@figurestyle\endcsname{OsF}
+
+\usepackage[biblatex]{embrac}
+\ChangeEmph{[}[,.02em]{]}[.055em,-.08em]
+\ChangeEmph{(}[-.01em,.04em]{)}[.04em,-.05em]
+
+\usepackage[accsupp]{acro}
+\acsetup{
+ long-format = \scshape ,
+ short-format = \scshape
+}
+\DeclareAcronym{ghs}{
+ short = ghs ,
+ long = Globally Harmonized System of Classification and Labelling of
+ Chemicals ,
+ pdfstring = GHS ,
+ accsupp = GHS
+}
+\DeclareAcronym{eu}{
+ short = EU ,
+ long = European Union ,
+ pdfstring = EU ,
+ accsupp = EU
+}
+\DeclareAcronym{iupac}{
+ short = iupac ,
+ long = International Union of Pure and Applied Chemistry ,
+ pdfstring = IUPAC ,
+ accsupp = IUPAC
+}
+\DeclareAcronym{UN}{
+ short = un ,
+ long = United Nations ,
+ pdfstring = UN ,
+ accsupp = UN
+}
+\DeclareAcronym{dvi}{
+ short = dvi ,
+ long = device independent file format ,
+ pdfstring = DVI ,
+ accsupp = DVO
+}
+\DeclareAcronym{pdf}{
+ short = pdf ,
+ long = portable document file ,
+ pdfstring = PDF ,
+ accsupp = PDF
+}
+\DeclareAcronym{id}{
+ short = id ,
+ long = identification string ,
+ pdfstring = ID ,
+ accsupp = ID
+}
+
+\chemsetup{
+ modules = {all,polymers} ,
+ greek = newtx ,
+ formula = chemformula ,
+ chemformula/format = \libertineLF
+}
+
+\usepackage{siunitx}
+
+\sisetup{
+ detect-mode=false,
+ mode=text,
+ text-rm=\libertineLF
+}
+
+\usepackage{filecontents}
+
+\defbibheading{bibliography}{\section{References}}
+\addbibresource{\jobname.bib}
+\begin{filecontents*}{\jobname.bib}
+@book{iupac:greenbook,
+ author = {E. Richard Cohan and Tomislav Cvita\v{s} and Jeremy G. Frey and
+ Bertil Holmstr\"om and Kozo Kuchitsu and Roberto Marquardt and Ian Mills and
+ Franco Pavese and Martin Quack and J\"urgen Stohner and Herbert L. Strauss and
+ Michio Takami and Anders J Thor} ,
+ title = {``Quantities, Symbols and Units in Physical Chemistry'', \acs{iupac}
+ Green Book} ,
+ shorttitle = {The \acs{iupac} Green Book} ,
+ sorttitle = {Quantities, Symbols and Units in Physical Chemistry} ,
+ indexsorttitle = {Quantities, Symbols and Units in Physical Chemistry} ,
+ edition = {3rd Edition. 2nd Printing} ,
+ year = {2008} ,
+ publisher = {\acs{iupac} \&\ RSC Publishing, Cambridge}
+}
+@book{iupac:redbook,
+ author = {Neil G. Connelly and Ture Damhus and Richard M. Hartshorn and
+ Alan T. Hutton} ,
+ title = {``Nomenclature of Inorganic Chemistry'', \acs{iupac} Red Book} ,
+ shorttitle = {The \acs{iupac} Red Book} ,
+ sorttitle = {Nomenclature of Inorganic Chemistry} ,
+ indexsorttitle = {Nomenclature of Inorganic Chemistry} ,
+ year = {2005} ,
+ publisher = { \acs{iupac} \&\ RSC Publishing, Cambridge} ,
+ isbn = {0-85404-438-8}
+}
+@book{iupac:bluebook,
+ author = {R. Panico and W. H. Powell and J-C. Richer},
+ title = {``Nomenclature of Organic Chemistry, Sections A, B, C, D, E, F,
+ and H'', \acs{iupac} Blue Book},
+ shorttitle = {The \acs{iupac} Blue Book} ,
+ sorttitle = {Nomenclature of Organic Chemistry} ,
+ indexsorttitle = {Nomenclature of Organic Chemistry} ,
+ edition = {\mkbibacro{draft}},
+ date = {2004-10-07},
+ url =
+ {http://old.iupac.org/reports/provisional/abstract04/BB-prs310305/CompleteDraft.pdf},
+ urldate = {2013-07-07}
+}
+@misc{eu:ghsystem_regulation,
+ author = {{The European Parliament and The Council of the European Union}},
+ sortname = {European Parliament and The Council of the European Union} ,
+ title = {Regulation (EC) No 1272/2008 of the European Parliament and of
+ the Council} ,
+ subtitle = {on classification, labelling and packaging of substances and
+ mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC, and
+ amending Regulation (EC) No 1907/2006} ,
+ journal = {Official Journal of the European Union} ,
+ date = {2008-12-16}
+}
+@online{unece:ghsystem_implementation,
+ author = {{United Nations Economic Commission for Europe}} ,
+ title = {GHS Implementation} ,
+ url =
+ {http://www.unece.org/trans/danger/publi/ghs/implementation_e.html} ,
+ urldate = {2012-03-20} ,
+ date = {2012-03-20}
+}
+@online{mychemistry:chemmacros-dev,
+ author = {Clemens Niederberger} ,
+ title = {chemmacros development} ,
+ url = {http://www.mychemistry.eu/2015/06/chemmacros-development/} ,
+ urldate = {2015-07-16} ,
+ date = {2015-06-14}
+}
+@online{mychemistry:modular-chemmacros,
+ author = {Clemens Niederberger} ,
+ title = {modular chemmacros} ,
+ url = {http://www.mychemistry.eu/2015/06/modular-chemmacros/} ,
+ urldate = {2015-07-16} ,
+ date = {2015-06-08}
+}
+@online{mychemistry:chemmacros-update-how,
+ author = {Clemens Niederberger} ,
+ title = {a new chemmacros -- but how?} ,
+ url = {http://www.mychemistry.eu/2015/07/a-new-chemmacros-but-how/} ,
+ urldate = {2015-07-16} ,
+ date = {2015-07-15}
+}
+\end{filecontents*}
+
+\DeclareInstance{xfrac}{chemformula-text-frac}{text}
+ {
+ scale-factor = 1 ,
+ denominator-bot-sep = -.2ex ,
+ denominator-format = \scriptsize #1 ,
+ numerator-top-sep = -.2ex ,
+ numerator-format = \scriptsize #1 ,
+ slash-right-kern = .05em ,
+ slash-left-kern = .05em
+ }
+
+\usetikzlibrary{calc,positioning,decorations.pathmorphing,patterns}
+
+% \newpackagename\chemmacros{chemmacros}
+\newcommand*\chemmacrosversion{\csname c_chemmacros_version_tl\endcsname}
+\newpackagename\chemformula{chemformula}
+\newpackagename\ghsystem{ghsystem}
+\newpackagename\chemgreek{chemgreek}
+
+\renewcommand*\AmS{\hologo{AmS}}
+\newcommand*\TikZ{Ti\textit{k}Z}
+\newcommand*\tablehead[1]{\textrm{\bfseries#1}}
+
+\providecommand*\XyM{%
+ X\kern-.30em
+ \smash{\raise.50ex\hbox{\char'7}}%
+ \kern-.30em M%
+}
+\providecommand*\XyMTeX{\XyM\kern-.1em\TeX}
+
+% \NewChemPhase{\aqi}{aq,$\infty$}% aqueous solution at infinite dilution
+% \NewChemPhase{\cd}{cd}% condensed phase
+% \NewChemPhase{\lc}{lc}% liquid crystal
+
+\newname\hensel{Martin Hensel}
+\newname\pedersen{Bj\o rn Pedersen}
+
+\newcommand*\iupaccs[3][]{%
+ \command{#2}[\quad\iupac{\csuse{#2}}]
+ #3\ifblank{#1}{}{\ifblank{#3}{}{ }An alias for this command is \cs{#1}.}%
+}
+
+% \undef\module
+% \undef\moduleidx
+\newidxcmd\chemmodule{\code{#1}}[ (module)]
+\newidxcmd\tikzdecoration{\code{#1}}[ (\TikZ\ decoration)]
+\AtEndPreamble{%
+ \pdfstringdefDisableCommands{%
+ \def\chemmodule*#1{\textquotedblleft#1\textquotedblright}%
+ }%
+}
+\newidxcmd\sym{\code{#1}}[ (symbol)]
+
+\makeatletter
+\def\cnltx@bash@listings@style{
+ language = bash,
+ basicstyle = {\sourceformat\color{black}},
+ % numbers = left,
+ % numberstyle = \tiny,
+ xleftmargin = 1em,
+ numbersep = .75em,
+ gobble = \cnltx@gobble ,
+ columns = fullflexible,
+ literate =
+ {ä}{{\"a}}1
+ {ö}{{\"o}}1
+ {ü}{{\"u}}1
+ {Ä}{{\"A}}1
+ {Ö}{{\"O}}1
+ {Ü}{{\"U}}1
+ {ß}{{\ss}}1 ,
+ breaklines = true,
+ keepspaces = true,
+ breakindent = 1em,
+ commentstyle = \color{comment},
+ keywordstyle = \color{black}\bfseries ,
+ stringstyle = \color{black} ,
+ showstringspaces = false ,
+ morekeywords = texdoc
+}
+
+\cnltx@expandargs(nx)\lstdefinestyle
+ {bash}
+ {\expandonce\cnltx@bash@listings@style}
+
+\newcommand*\prompt{}
+\patchcmd\lst@NewLine
+ {\hbox{}}% search
+ {\hbox{}\prompt}% replace
+ {}% success
+ {}% failure
+\newsourcecodeenv[
+ code-only,
+ sourcecode-options = {
+ style = bash ,
+ deleteindex = [5][keyword5] ,
+ deleteindex = [6][keyword6]
+ },
+ pre-code = \def\prompt{\textasciitilde\space\$\space}
+]{lbash}
+\makeatother
+
+\renewcommand*\dictumauthorformat[1]{#1}
+\renewcommand*\raggeddictumtext{}
+
+\newcommand*\TF{\textcolor{red}{\uline{\code{\textcolor{cs}{\textit{TF}}}}}}
+
+\makeatletter
+\newrobustcmd*\explcsformat[1]{%
+ \code{\textbackslash\textcolor{cs}{\detokenize{#1}}}%
+}
+\newidxcmd\explcs{\explcsformat{#1}}[ (expl3)]
+
+\cnltx@deflistitem{\cnltx@explcommand}{\explcs}
+\renewenvironment{commands}
+ {%
+ \let\command\cnltx@command
+ \let\explcommand\cnltx@explcommand
+ \cnltxlist
+ }
+ {\endcnltxlist}
+\newenvironment{tikzcode}
+ {%
+ \def\arrowtip{\@cnltx@option@item\code}%
+ \cnltxlist
+ }
+ {\endcnltxlist}
+
+\newrobustcmd*\showenv[1]{\beginenv*\code{\{}\env{#1}\code{\}}}
+\makeatother
+
+\ExplSyntaxOn
+\cs_new_protected:Npn \chemboldchecks #1
+ {
+ \seq_set_map:NNn \l_tmpa_seq \l__chemmacros_if_bf_seq { \code {##1} }
+ \seq_use:Nnnn \l_tmpa_seq {,~} {,~} {~#1~}
+ }
+\ExplSyntaxOff
+
+\AtBeginDocument{\renewcommand*\reftextfaraway[1]{starting on page~\pageref{#1}}}
+
+\usepackage{bookmark}
+
+\begin{document}
+
+\part{Preliminaries}
+\section{Licence, Requirements and \textsc{README}}\label{sec:licence-requ-readme}
+\license
+
+\chemmacros\ loads the packages \pkg{expl3}~\cite{bnd:l3kernel} and
+\pkg{xparse}~\cite{bnd:l3packages}. Depending on your usage other packages
+will be loaded. They are mentioned when the corresponding module using the
+package is described.
+
+\section{Motivation and Background}\label{sec:motiv-backgr}
+This package grew from a small collection of personal helper macros back
+in~2010 into a rather big package supporting various different chemical
+typesetting tasks. I hope I have achieved the following points with this
+package:
+\begin{itemize}
+ \item Intuitive usage as far as the syntax of the commands is concerned.
+ \item A comprehensive set of macros! If there are any needs you might have
+ with respect to typesetting of chemistry which is not supported by this
+ package\footnote{Not including needs already solved by other packages such
+ as \pkg{chemnum} or \pkg{chemfig}.} then let me know so \chemmacros\ can
+ be extended.
+ \item The commands shall not only make typesetting easier and faster but
+ also the document source more readable with respect to semantics
+ (\code{\cs{ortho}-dichlorobenzene} is easier to read and understand than
+ \code{\cs*{textit}\Marg{o}-dichlorobenzene}); the first variant in my
+ opinion also is more in the spirit of \LaTeXe.
+ \item As much customizability as I could think of so every user can adapt
+ the commands to his or her own wishes. Every now and then users have
+ wishes which can't be solved with the available options. Almost always
+ I'll add options then. If you find something please contact me, see
+ section~\vref{sec:sugg-bug-reports}.
+ \item Default settings that are compliant with the recommendations of the
+ \acf{iupac}.
+\end{itemize}
+Especially the last point in the past needed some pushing from users to get
+things right in many places. If you find anything not compliant with
+\ac{iupac} recommendations please contact me, see
+section~\vref{sec:sugg-bug-reports}. Don't forget to add references for the
+corresponding \ac{iupac} recommendation.
+
+\section{The Structure of \chemmacros}\label{sec:structure-chemmacros}
+\subsection{General Structure}
+Since version~5.0 the \chemmacros\ package has a strictly modular
+structure\sinceversion{5.0}. On the one hand this eases maintenance but it
+will also allow for easy and quick extension in the future. In a way it is a
+logical consequence from \chemmacros' history: since version~2.0, \ie, since
+the fall of~2011 \chemmacros\ already had modular options.
+
+The different modules of \chemmacros\ are divided into two groups:
+\begin{enumerate}
+ \item Internal modules which provide underlying functionality or basic
+ functionality which is not of direct interest from a user perspective but
+ might be if you plan to write a module yourself (see
+ section~\ref{sec:own-modules} for details).
+ \item User modules which provide all the stuff for typesetting.
+\end{enumerate}
+Both groups each are subdivided into two groups: preloaded modules and modules
+which have to be loaded by the programmer (internal modules) or by the
+document author (user modules). Those modules are described in
+parts~\ref{part:preloaded-modules} (preloaded modules)
+and~\ref{part:additional-modules} (additional modules) of this manual.
+
+The above means that not all functionality is available per default. If you
+want to load \emph{all} modules no matter what then you can say:
+\begin{sourcecode}
+ \usechemmodule{all}
+\end{sourcecode}
+or
+\begin{sourcecode}
+ \chemsetup{modules=all}
+\end{sourcecode}
+which will load all modules which are part of \chemmacros\ (also see
+section~\vref{sec:all-module}). Own modules (see
+section~\vref{sec:own-modules}) are \emph{not} loaded through this, though,
+and still have to be loaded additionally.
+
+In part~\vref{part:preloaded-modules} the preloaded modules are described,
+first the user modules then the internal ones, in
+part~\vref{part:additional-modules} the other available modules are described,
+again the user modules first. In each section the modules are described in
+an alphabetical order.
+
+\subsection{Using \chemmacros' Options}\label{sec:using-chemm-opti}
+Prior to v5.0 \chemmacros\ had quite a number of package options.
+\chemmacros\ v5.0 or higher has none! All of \chemmacros' options are set
+using the command
+\begin{commands}
+ \command{chemsetup}[\oarg{module}\marg{option list}]
+ \chemmacros' setup command.
+\end{commands}
+
+When an option is described then in the left margin the module the option
+belongs to is denoted. This looks something like this:
+\begin{options}
+ \keyval{option}{value}\Module{module}\Default
+ Description of \option{option}. The module is printed in the left margin.
+ The default value to the right is the setting the option has when
+ \chemmacros\ is loaded. This can be an explicit setting but the option
+ can also be empty.
+ \keychoice{choice-option}{list,of,\default{choices}}\Module{module}\Default{list}
+ Description of \option{choice-option}. A choice option can only be used
+ with a predefined list of values. If one of the values is underlined it
+ means that the option can be used without value in which case the
+ underlined value is chosen. If no value is underlined then a value
+ \emph{has} to be given by the user.
+ \keybool{boolean-option}\Module{module}\Default{true}
+ Description of \option{boolean-option}. A boolean option is a choice
+ option with exactly the two values \code{true} and \code{false}. If the
+ option is called without value then the underlined value is chosen (which
+ is always \code{true} for a boolean option).
+\end{options}
+
+An option or list of options belonging to a module \chemmodule{module} can be
+set in two ways:
+\begin{sourcecode}
+ % first possibility:
+ \chemsetup[module]{
+ option1 = value ,
+ option2 = value
+ }
+ % second possibility:
+ \chemsetup{
+ module/option1 = value ,
+ module/option2 = value
+ }
+\end{sourcecode}
+The second way allows to set options belonging to different modules with one
+call of \cs{chemsetup}.
+
+\subsection{Support Package \chemformula}
+\chemformula\ provides means of typesetting chemical formulas and reactions.
+You will see its macros \cs{ch} and \cs{chcpd} every now and then in this
+manual. When using \chemmacros\ you can consider the \chemformula\
+package~\cite{pkg:chemformula} to be loaded as \chemmacros\ makes use of it in
+various places. \chemmacros\ and \chemformula\ are tightly intertwined.
+Nevertheless you should be able to use the \pkg{mhchem}~\cite{pkg:mhchem}
+package with \chemmacros. Please see section~\vref{sec:using-mhchem} for
+details and \latin{caveat}s. \emph{The recommendation is to use
+ \chemformula.}
+
+A historical note: \chemformula\ started as a part of \chemmacros\ in
+January~2012. Since July~2013 it is a completely independent package -- from
+\chemformula's point of view. It is maintained independently and has a manual
+of its own.
+
+\subsection{Upgrading from version $<5.0$}
+People upgrading from versions $<5.0$ will find that almost everything they
+know from earlier versions is the same in versions $\geq5.0$. But there are
+important and \emph{breaking} differences:
+\begin{itemize}
+ \item \chemmacros\ has no package options any more, all options are set via
+ \cs{chemsetup}, also see section~\vref{sec:using-chemm-opti}.
+ \item Not all of the features are available per default any more, for some
+ the corresponding module has to be loaded explicitly, see
+ section~\ref{sec:general-options}. If suddenly some commands or
+ environments seem to be undefined this is the most likely reason.
+ \item Some option modules have been renamed (\eg, \module*{iupac} is now
+ \module{nomenclature}). If you experience strange errors when you upgrade
+ your document this is the most likely source.
+ \item The command family \cs*{NewChem\ldots}, \cs*{RenewChem\ldots} and
+ \cs*{DeclareChem\ldots} has a new member \cs*{ProvideChem\ldots}.
+ \item In \cs{iupac} the macro \cs*{-} no longer gives a dash with breaking
+ point. Instead \sym*{-} can be used directly\footnote{\cs*{-} is provided
+ up to and including v5.2 but is dropped in higher versions.}.
+ \item The macro \cs{ox} has another default behaviour (\keyis{pos}{super})
+ and the starred version has another effect (\keyis{pos}{top}) than the
+ same macro in earlier versions. Now the default behaviour follows
+ \acs{iupac} recommendations. A second change is that the atom is now
+ treated as a \chemformula\ input (this depends on the setting of the
+ \option{formula} option, see~\vref{sec:chemformula-module}).
+ \item The syntax of \cs{NewChemReaction} and friends is now different from
+ what it used to be. If you have defined your own reaction environments
+ you need to adapt!
+ \item \chemmacros\ offers a macro \cs{state} which is similar to but
+ different from the earlier macro \cs*{State}. \cs*{State} is deprecated.
+ There are also differences in the syntax of \cs{enthalpy} \vs\ the earlier
+ \cs*{Enthalpy}, \cs{entropy} \vs\ \cs*{Entropy} and \cs{gibbs} \vs\
+ \cs*{Gibbs}. The uppercase versions are deprecated. The macro
+ \cs{NewChemState} also has a different syntax now.
+ \item At various places in the code improvements and fixes have been made,
+ too many to list them here. You should keep an open eye and first of all
+ read the manual closely.
+\end{itemize}
+
+\subsection{Compatibility Mode}
+
+\subsubsection{For Users}
+It is actually not true that \chemmacros' has no package options any more. It
+has one very important package option:
+\begin{options}
+ \keychoice{compatibility}{\meta{version},newest,latest}\Default{\chemmacrosversion}
+ Let's you specify the version of \chemmacros\ you want to use. Any
+ version earlier than 5.0 will load v4.7. \ie, the last version before
+ \chemmacros\ got its modular structure\footnote{Mostly: the loaded v4.7
+ has got a few fixes}. Not using the option will always load the newest
+ version.
+
+ Both values \code{newest} and \code{latest} will choose the latest version
+ available.
+\end{options}
+
+In your document you can check for the compatibility mode. For the following
+functions it is important to understand the rules: \emph{greater} means
+\emph{newer}. The version number is \emph{not} a usual decimal number! The
+syntax for \meta{version} is \meta{major}\code{.}\meta{minor}\meta{optional
+ subrelease}. This means that a version~5.11 is \emph{newer} than a
+version~5.7! In the same way \emph{less} means \emph{older}. As last
+example: 5.10~is \emph{newer} (greater) than~5.1. \meta{optional subrelease}
+is a lowercase letter which might or might not be present in a version number.
+Version~5.7b is newer than~5.7a which in turn is newer than~5.7.
+\begin{commands}
+ \expandable\command{IfChemCompatibilityTF}[\marg{comp}\marg{version}%
+ \marg{true}\marg{false}]
+ Checks the value given through the option \option{compatibility} against
+ \meta{version} using \meta{comp} and either leaves \meta{true} or
+ \meta{false} in the input stream. \meta{comp} can be one of \code{<},
+ \code{<=}, \code{=}, \code{>=} or \code{>}.
+ \expandable\command{IfChemCompatibilityT}[\marg{comp}\marg{version}\marg{true}]
+ Checks the value given through the option \option{compatibility} against
+ \meta{version} using \meta{comp} and leaves \meta{true} in the input
+ stream if the check is logically true. \meta{comp} can be one of
+ \code{<}, \code{<=}, \code{=}, \code{>=} or \code{>}.
+ \expandable\command{IfChemCompatibilityF}[\marg{comp}\marg{version}\marg{false}]
+ Checks the value given through the option \option{compatibility} against
+ \meta{version} using \meta{comp} and leaves \meta{false} in the input
+ stream if the check is logically false. \meta{comp} can be one of
+ \code{<}, \code{<=}, \code{=}, \code{>=} or \code{>}.
+\end{commands}
+
+A possible usage:
+\begin{sourcecode}
+ \IfChemCompatibilityT{>=}{5.0}{\usechemmodule{all}}
+\end{sourcecode}
+
+Loading \chemmacros\ with \keyis{compatibility}{4.7} also allows to use the
+package options from that version:
+\begin{sourcecode}
+ \usepackage[compatibility=4.7,language=german]{chemmacros}
+\end{sourcecode}
+
+\subsubsection{For Module Writers}
+For future versions the aim is not to make such breaking changes again. While
+we never know what the future actually will bring \chemmacros\ now has the
+tools for tying code to a version number:
+\begin{commands}
+ \expandable\explcommand{chemmacros_if_compatibility:nn}[\TF\ \marg{comp}
+ \marg{version} \marg{true} \marg{false}]
+ expl3 version of \cs{IfChemCompatibilityTF}.
+\end{commands}
+
+In modules one can try adding code for a certain version or range of versions:
+\begin{commands}
+ \command{ChemCompatibility}[\marg{version} \meta{code} \cs{EndChemCompatibility}]
+ Leaves \meta{code} in the input stream if the compatibility version $x$
+ given by \option{compatibility} matches \meta{version}
+ ($x=\text{\meta{version}}$).
+ \command{ChemCompatibilityFrom}[\marg{version} \meta{code} \cs{EndChemCompatibility}]
+ Leaves \meta{code} in the input stream if the compatibility version $x$
+ given by \option{compatibility} matches \meta{version} or newer. This
+ means \meta{version} is the \emph{oldest} version allowed
+ ($x\geq\text{\meta{version}}$).
+ \command{ChemCompatibilityTo}[\marg{version} \meta{code} \cs{EndChemCompatibility}]
+ \changedversion{5.8a}Leaves \meta{code} in the input stream if the
+ compatibility version $x$ given by \option{compatibility} matches any
+ version up to and \emph{excluding} \meta{version}. This means
+ \meta{version} is the \emph{oldest} version \emph{not} allowed
+ ($x<\text{\meta{version}}$).
+ \command{ChemCompatibilityBetween}[\marg{version 1}\marg{version 2} \meta{code}
+ \cs{EndChemCompatibility}]
+ \changedversion{5.8a}Leaves \meta{code} in the input stream if the
+ compatibility version $x$ given by \option{compatibility} lies between and
+ \emph{including} \meta{version 1} up to and \emph{excluding} \meta{version 2}
+ ($\text{\meta{version 1}}\leq x<\text{\meta{version 2}}$).
+ \command{EndChemCompatibility}
+ This macro \emph{must} end each of the \cs*{ChemCompatibility\ldots}
+ macros.
+\end{commands}
+
+You may refer to the current version of \chemmacros\ with the following
+tokenlists:
+\begin{commands}
+ \explcommand{c_chemmacros_date_tl}
+ The current release date: \enquote{\csname
+ c_chemmacros_date_tl\endcsname}.
+ \explcommand{c_chemmacros_version_major_number_tl}
+ The current major version: \enquote{\csname
+ c_chemmacros_version_major_number_tl\endcsname}.
+ \explcommand{c_chemmacros_version_minor_number_tl}
+ The current minor version: \enquote{\csname
+ c_chemmacros_version_minor_number_tl\endcsname}.
+ \explcommand{c_chemmacros_version_number_tl}
+ The current version number: \enquote{\csname
+ c_chemmacros_version_number_tl\endcsname}.
+ \explcommand{c_chemmacros_version_subrelease_tl}
+ The current sub-release: \enquote{\csname
+ c_chemmacros_version_subrelease_tl\endcsname}.
+ \explcommand{c_chemmacros_version_tl}
+ The current version: \enquote{\csname c_chemmacros_version_tl\endcsname}.
+ \explcommand{c_chemmacros_info_tl}
+ The package information: \enquote{\csname
+ c_chemmacros_info_tl\endcsname}.
+\end{commands}
+
+\section{General Options}\label{sec:general-options}
+
+\chemmacros\ has some core options which don't belong to any of the modules
+described in parts~\ref{part:preloaded-modules}
+and~\ref{part:additional-modules}. Those options have no module denoted in
+the left margin next to their descriptions and are also set without specifying
+a module:
+\begin{sourcecode}
+ \chemsetup{
+ option1 = value ,
+ option2 = value
+ }
+\end{sourcecode}
+
+Two of those options are explained now:
+\begin{options}
+ \keyval{modules}{comma separated list of module names}\Default
+ With this option you can specify which modules you want to load.
+ Alternatively you can use \cs{usechemmodule}\marg{comma separated list of
+ module names}.
+ \keyval{greek}{mapping}\Default
+ Explicitly specify which mapping should be used by the \chemgreek\
+ package~\cite{pkg:chemgreek}. For details about what this means please
+ refer to section~\vref{sec:greek-module}.
+\end{options}
+
+Some internal modules may also define core options, \eg, the \chemmodule{lang}
+module, see section~\vref{sec:lang-module}.
+
+\part{The Preloaded Modules}\label{part:preloaded-modules}
+
+\section{User Modules}
+\subsection{The \chemmodule*{acid-base} Module}\label{sec:acid-base-module}
+
+Easy representation of \pH, \pKa \ldots
+\begin{commands}
+ \command{pH} \pH
+ \command{pOH} \pOH
+ \command{Ka} \Ka, depends on language settings, see
+ section~\vref{sec:lang-module}. The translations can be adapted.
+ \command{Kb} \Kb
+ \command{Kw} \Kw
+ \command{pKa}[\oarg{num}] \cs{pKa}: \pKa, \cs{pKa}\Oarg{1}: \pKa[1], depends
+ on language settings, see section~\vref{sec:lang-module}. The translations
+ can be adapted.
+ \command{pKb}[\oarg{num}] \cs{pKb}: \pKb, \cs{pKb}\Oarg{1}: \pKb[1]
+ \command{p}[\marg{anything}] \eg\ \cs{p}\Marg{\cs{Kw}} \p{\Kw}
+\end{commands}
+
+\begin{example}[side-by-side]
+ \Ka\ \Kb\ \pKa\ \pKa[1] \pKb\ \pKb[1]
+\end{example}
+
+\begin{cnltxquote}[{\citetitle{iupac:greenbook} \cite[][p.\,103]{iupac:greenbook}}]
+ The operator \p{} \textelp{} shall be printed in Roman type.
+\end{cnltxquote}
+
+There is one option which changes the style the \p{} is typeset, other options
+allow to change the subscript of the constants:
+\begin{options}
+ \keychoice{p-style}{italics,slanted,upright}\Module{acid-base}\Default{upright}
+ Set the style of the \p{} operator.
+ \keyval{K-acid}{text}\Module{acid-base}\Default{\cs{ChemTranslate}\Marg{K-acid}}
+ The subscript to \cs{Ka} and \cs{pKa}.
+ \keyval{K-base}{text}\Module{acid-base}\Default{\cs{ChemTranslate}\Marg{K-base}}
+ The subscript to \cs{Kb} and \cs{pKb}.
+ \keyval{K-water}{text}\Module{acid-base}\Default{\cs{ChemTranslate}\Marg{K-water}}
+ The subscript to \cs{Kw}.
+ \keyval{eq-constant}{text}\Module{acid-base}\Default{K}
+ The\sinceversion{5.4} symbol of the constants.
+\end{options}
+\begin{example}
+ \pH, \pKa \par
+ \chemsetup[acid-base]{p-style=slanted} \pH, \pKa \par
+ \chemsetup[acid-base]{p-style=italics} \pH, \pKa
+\end{example}
+
+As you can see the default subscripts of \cs{Kw}, \cs{Ka} and \cs{Kb} are
+lowercase letters. The literature is inconclusive about if this is the right
+way or if uppercase letters should be preferred. In textbooks the uppercase
+variant usually seems to be used while journals seem to prefer the lowercase
+variant. \chemmacros' default follows the usage in
+\citetitle{iupac:greenbook}~\cite{iupac:greenbook}. If you want to change
+this you have two possibilities:
+
+\begin{example}
+ % this works only in the preamble:
+ % \DeclareTranslation{English}{K-acid}{\mathrm{A}}% use your language here
+ % alternative:
+ \chemsetup{acid-base/K-acid=\mathrm{A}}% overwrites language dependent settings
+ \pKa
+\end{example}
+
+The\sinceversion{5.4} constants \Ka, \Kb, and \Kw\ were defined using the
+following commands:
+\begin{commands}
+ \command{NewChemEqConstant}[\marg{cs}\marg{name}\marg{subscript}]
+ Define the constant \meta{cs} with the name \meta{name} and the subscript
+ \meta{subscript}. This also defines the default translation with the key
+ \meta{name} using \meta{subscript} as fallback translation (see
+ section~\vref{sec:lang-module} for details). It also defines the option
+ \meta{name} for setting the subscript.
+ \command{RenewChemEqConstant}[\marg{cs}\marg{name}\marg{default appearance}]
+ The same as \cs{NewChemEqConstant} but renews an existing command.
+ \command{DeclareChemEqConstant}[\marg{cs}\marg{name}\marg{default appearance}]
+ The same as \cs{NewChemEqConstant} but overwrites existing commands.
+ \command{ProvideChemEqConstant}[\marg{cs}\marg{name}\marg{default appearance}]
+ The same as \cs{NewChemEqConstant} but doesn't throw an error if \meta{cs}
+ already exists.
+\end{commands}
+
+This is how \cs{Ka} is defined:
+\begin{sourcecode}
+ \NewChemEqConstant\Ka{K-acid}{\mathrm{a}}
+\end{sourcecode}
+
+\subsection{The \chemmodule*{charges} Module}\label{sec:charges-module}
+
+The \chemmodule{charges} module loads the module \chemmodule{chemformula}.
+
+\subsubsection{Charge Symbols}
+\begin{commands}
+ \command{fplus} \fplus\ formal positive charge
+ \command{fminus} \fminus\ formal negative charge
+ \command{scrp} \scrp\ scriptstyle positive charge (\eg, for usage in
+ \pkg{chemfig}'s~\cite{pkg:chemfig} formulas).
+ \command{scrm} \scrm\ scriptstyle negative charge (\eg, for usage in
+ \pkg{chemfig}'s formulas).
+ \command{fscrp} \fscrp\ scriptstyle formal positive charge (\eg, for usage
+ in \pkg{chemfig}'s formulas).
+ \command{fscrm} \fscrm\ scriptstyle formal negative charge (\eg, for usage
+ in \pkg{chemfig}'s formulas).
+ \command{fsscrp} \fsscrp\ scriptscriptstyle formal positive charge (\eg, for
+ usage in \pkg{chemfig}'s formulas).
+ \command{fsscrm} \fsscrm\ scriptscriptstyle formal negative charge (\eg, for
+ usage in \pkg{chemfig}'s formulas).
+\end{commands}
+
+\subsubsection{Ion Charges}\label{sec:ion-charges}
+Simple displaying of (real) charges. It is worth noting that these commands
+really are relicts from a time when \chemmacros\ tried hard to be compliant
+with \pkg{mhchem} and \chemformula\ didn't exist, yet. \textbf{They are still
+ provided for backwards compatibility but \emph{my recommendation is to use}
+ \cs{ch} (see the documentation of the \chemformula\
+ package~\cite{pkg:chemformula}) \emph{and forget about these commands:}}
+\begin{commands}
+ \command{pch}[\oarg{number}]
+ positive charge
+ \command{mch}[\oarg{number}]
+ negative charge
+ \command{fpch}[\oarg{number}]
+ formal positive charge
+ \command{fmch}[\oarg{number}]
+ formal negative charge
+\end{commands}
+\begin{example}[side-by-side]
+ A\pch\ B\mch[3] C\fpch[2] D\fmch
+\end{example}
+
+\subsubsection{Partial Charges and Similar Stuff}\label{sec:part-charg-simil}
+
+The next ones probably are seldomly needed but nevertheless useful:
+\begin{commands}
+ \command{delp} \delp\ partial positive charge
+ \command{delm} \delm\ partial negative charge
+ \command{fdelp} \fdelp\ partial formal positive charge
+ \command{fdelm} \fdelm\ partial formal negative charge
+\end{commands}
+
+These macros for example can be used with the \cs{ox} command (see
+section~\vref{sec:redox-module}) or with the \pkg{chemfig} package:
+\begin{example}
+ \chemsetup{
+ charges/circled = all,
+ redox/parse = false,
+ redox/pos = top
+ }
+ \ch{"\ox{\delp,H}" -{} "\ox{\delm,Cl}"} \hspace*{1cm}
+ \chemfig{\chemabove[3pt]{\lewis{246,Br}}{\delm}-\chemabove[3pt]{H}{\delp}}
+\end{example}
+
+\subsubsection{Charge Options}
+
+\begin{options}
+ \keychoice{circled}{formal,\default{all},none}\Module{charges}\Default{formal}
+ \chemmacros\ uses two different kinds of charges which indicate the usage
+ of real ($+/-$) and formal (\fplus/\fminus) charges. The option
+ \code{formal} distinguishes between them, option \code{none} displays them
+ all without circle, option \code{all} circles all.
+ \keychoice{circletype}{chem,math}\Module{charges}\Default{chem}
+ This option switches between two kinds of circled charge symbols:
+ \cs{fplus} \fplus/\cs{fminus} \fminus\ (\code{chem}) and
+ \verbcode+$\oplus$+ $\oplus$/\verbcode+$\ominus$+ $\ominus$ (\code{math}).
+ \keyval{partial-format}{\LaTeX\ code}\Module{charges}\Default{\cs*{tiny}}
+ Code which formats the macros defined with \cs{NewChemPartialCharge} (see
+ section~\ref{sec:own-charge-macros}).
+\end{options}
+
+\subsubsection{Own Charge Macros}\label{sec:own-charge-macros}
+Just in case the existing macros don't fit you needs there are commands for
+defining new ones or modifying the existing ones. These commands define
+macros like those described in section~\vref{sec:ion-charges}.
+
+\begin{commands}
+ \command{NewChemCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a new macro \meta{cs}. Raises an error if \meta{cs} already
+ exists.
+ \command{RenewChemCharge}[\marg{cs}\marg{charge symbol}]
+ Redefines a new macro \meta{cs}. Raises an error if \meta{cs} doesn't
+ exist.
+ \command{DeclareChemCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a macro \meta{cs}. Silently overwrites \meta{cs} if it exists.
+ \command{ProvideChemCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a new macro \meta{cs}. Does nothing if \meta{cs} already exists.
+\end{commands}
+An example of usage is the definition of the existing ion charge macros:
+\begin{sourcecode}
+ \NewChemCharge\fpch{\fplus}
+ \NewChemCharge\fmch{\fminus}
+\end{sourcecode}
+
+These commands define macros like those described in
+section~\vref{sec:part-charg-simil}.
+\begin{commands}
+ \command{NewChemPartialCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a new macro \meta{cs}. Raises an error if \meta{cs} already
+ exists.
+ \command{RenewChemPartialCharge}[\marg{cs}\marg{charge symbol}]
+ Redefines a new macro \meta{cs}. Raises an error if \meta{cs} doesn't
+ exist.
+ \command{DeclareChemPartialCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a macro \meta{cs}. Silently overwrites \meta{cs} if it exists.
+ \command{ProvideChemPartialCharge}[\marg{cs}\marg{charge symbol}]
+ Defines a new macro \meta{cs}. Does nothing if \meta{cs} already exists.
+\end{commands}
+An example of usage is the definition of the existing partial charge macros:
+\begin{sourcecode}
+ \NewChemPartialCharge\fdelp{\fplus}
+ \NewChemPartialCharge\fdelm{\fminus}
+\end{sourcecode}
+
+\subsection{The \chemmodule*{nomenclature} Module}\label{sec:nomenclature-module}
+
+The \chemmodule{nomenclature} module loads the \chemmodule{tikz} module. It
+also loads the package \pkg{scrlfile} which is part of the
+\KOMAScript\ bundle~\cite{bnd:koma-script}.
+
+\subsubsection{The \cs*{iupac} Command}
+
+Similar to the \pkg{bpchem} package~\cite{pkg:bpchem} \chemmacros\ provides a
+command\footnote{The idea and initial implementation is shamelessly borrowed
+ from \pkg{bpchem} by \pedersen.} for typesetting \ac{iupac} names. Why is
+that useful? \ac{iupac} names can get very long. So long indeed that they
+span over more than two lines, especially in two-column documents. This means
+they must be allowed to be broken more than one time. This is what the
+following command does.
+\begin{commands}
+ \command{iupac}[\marg{IUPAC name}]
+ Inside this command use \sym{\textbar} indicate a breaking point
+ \sym{\textasciicircum} as a shortcut for \cs*{textsuperscript}. \sym{-},
+ \sym{(} and \sym{)} allow words to be broken while still allow the rest of
+ word to be hyphenated, likewise \sym{[} and \sym{]}.
+\end{commands}
+
+\begin{example}
+ \begin{minipage}{.4\linewidth}
+ \iupac{%
+ Tetra|cyclo[2.2.2.1^{1,4}]-un|decane-2-dodecyl-%
+ 5-(hepta|decyl|iso|dodecyl|thio|ester)%
+ }
+ \end{minipage}
+\end{example}
+
+The \cs{iupac} command is more of a semantic command. In many cases you can
+achieve (nearly) the same thing by using \cs*{-} instead of \sym{\textbar},
+and \cs*{textsuperscript} instead of \sym{\textasciicircum} without
+\cs{iupac}. There are some important differences, though:
+\begin{itemize}
+ \item The character \sym{-} inserts a small space before the hyphen and
+ removes a small space after it. Also usually words with hyphens are only
+ allowed to break at the hyphen. Inside \cs{iupac} the hyphen will not
+ prevent further hyphenation. The amount of inserted space can be
+ customized.
+ \item The character \sym{\textbar} not only prevents ligatures but also
+ inserts a small space. The amount of inserted space can be customized.
+ \item The characters \sym{(} and \sym{)} allow the word to be hyphenated and
+ don't prevent further hyphenation, likewise \sym{[} and \sym{]}.
+ \item \sinceversion{5.3}The character \sym{'} is printed as \cs{chemprime}.
+\end{itemize}
+\begin{example}[side-by-side]
+ \huge\iupac{2,4-Di|chlor|pentan} \par
+ 2,4-Dichlorpentan
+\end{example}
+\begin{commands}
+ \command{chemprime}
+ Prints\sinceversion{5.3} a prime character in superscript position. It is
+ defined as \verbcode+\ensuremath{{}^{\prime}}+.
+\end{commands}
+
+The spaces inserted by \sym{-} and \sym{\textbar} can be
+customized.
+\begin{options}
+ \keyval{hyphen-pre-space}{dim}\Module{nomenclature}\Default{.01em}
+ Set the space that is inserted before the hyphen set with \sym{-}.
+ \keyval{hyphen-post-space}{dim}\Module{nomenclature}\Default{-.03em}
+ Set the space that is inserted after the hyphen set with \sym{-}.
+ \keyval{break-space}{dim}\Module{nomenclature}\Default{.01em}
+ Set the space inserted by \sym{\textbar}.
+\end{options}
+
+The command \cs{iupac} serves another purpose, too, however. Regardless of
+the setting of the \option{iupac} option (see below) all the commands
+presented in this section are always defined \emph{inside} \cs{iupac}. Quite
+a number of the naming commands have very general names: \cs{meta}, \cs{D},
+\cs{E}, \cs{L}, \cs{R}, \cs{S}, \cs{trans} and so forth\footnote{Please read
+ section~\vref{sec:one-letter-commands} before you consider using the
+ one-letter commands}. This means they either are predefined already (\cs{L}
+\L) or are easily defined by another package or class (the \pkg{cool} package
+defines both \cs{D} and \cs{E}, for example). In order to give you control
+which commands are defined in which way, there is the option \option{iupac}:
+\begin{options}
+ \keychoice{iupac}{auto,restricted,strict}\Module{nomenclature}\Default{auto}
+ Take care of how \ac{iupac} naming commands are defined.
+\end{options}
+It has three modes:
+\begin{itemize}
+ \item \keyis{iupac}{auto}: if the commands are \emph{not} defined by any
+ package or class you're using they are available generally, otherwise only
+ \emph{inside} \cs{iupac}.
+ \item \keyis{iupac}{restricted}: all naming commands are \emph{only} defined
+ inside \cs{iupac}. If the commands are defined by another package they of
+ course have that meaning outside. They're not defined outside otherwise.
+ \item \keyis{iupac}{strict}: \chemmacros\ overwrites any other definition and
+ makes the commands available throughout the document. Of course the
+ commands can be redefined (but only in the document body). They will still
+ be available inside \cs{iupac} then.
+\end{itemize}
+Table~\vref{tab:iupac_modes} demonstrates the different modes.
+
+\begin{table}
+ \centering
+ \caption{Demonstration of \option*{iupac}'s modes.}\label{tab:iupac_modes}
+ \begin{tabular}{lccc}
+ \toprule
+ & auto & restricted & strict \\
+ \midrule
+ \cs{L} & \L & \L & \iupac{\L} \\
+ \cs{iupac}\Marg{\cs{L}} & \iupac{\L} & \iupac{\L} & \iupac{\L} \\
+ \cs{D} & \D & --- & \D \\
+ \cs{iupac}\Marg{\cs{D}} & \iupac{\D} & \iupac{\D} & \iupac{\D} \\
+ \bottomrule
+ \end{tabular}
+\end{table}
+
+\subsubsection{Macros Defined (Not Only) For Usage in \cs*{iupac}}
+
+\paragraph{One-letter Macros}\label{sec:one-letter-commands}
+For some of the macros explained in this section one-letter commands are
+defined -- with a \latin{caveat} in mind, though: they are not actively
+recommended. One-letter commands seldomly have meaningful names and often
+they've also been defined by other packages. This means they make
+collaboration more difficult than it needs to be and are a source for package
+conflicts. \chemmacros\ solves the latter problem by only providing them
+inside the argument of \cs{iupac}. The one exception \chemmacros\ makes is
+the command \cs{p} (for things like \pH) which is and will remain an official
+command (see section~\vref{sec:acid-base-module}). For all other one-letter
+macros alternatives with more meaningful names exist.
+
+\paragraph{Greek Letters}\label{par:greek_letters}
+
+Greek letters in compound names are typeset upright. Here are a few examples
+for the existing macros:
+\begin{commands}
+ \command{chemalpha}[\quad\chemalpha]
+ Upright lowercase alpha
+ \command{chembeta}[\quad\chembeta]
+ Upright lowercase alpha
+ \command{chemgamma}[\quad\chemgamma]
+ Upright lowercase alpha
+ \command{chemdelta}[\quad\chemdelta]
+ Upright lowercase alpha
+\end{commands}
+There exist two commands for each of the twenty-four Greek letters: a
+lowercase and an uppercase version (\cs{chemalpha} and \cs{chemAlpha}). Those
+commands are actually provided by the \chemgreek\ package. For more details
+read section~\vref{sec:greek-module} and also refer to \chemgreek's
+documentation.
+
+There are a number of one-letter commands that some people may find convenient
+to use which use above mentioned commands to print Greek letters inside
+\cs{iupac}. They're listed in table~\vref{tab:iupac-greek-shortcuts}.
+
+\begin{table}
+ \centering
+ \caption{\acs*{iupac} shortcuts for Greek letters.}
+ \label{tab:iupac-greek-shortcuts}
+ \begin{tabular}{*9l}
+ \toprule
+ macro &
+ \cs{a} & \cs{b} & \cs{g} & \cs{d} &
+ \cs{k} & \cs{m} & \cs{n} & \cs{w} \\
+ \midrule
+ letter &
+ \iupac{\a} & \iupac{\b} & \iupac{\g} & \iupac{\d} &
+ \iupac{\k} & \iupac{\m} & \iupac{\n} & \iupac{\w} \\
+ \bottomrule
+ \end{tabular}
+\end{table}
+
+\begin{example}
+ \iupac{5\chemalpha-androstan-3\chembeta-ol} \par
+ \iupac{\chemalpha-(tri|chloro|methyl)-\chemomega
+ -chloro|poly(1,4-phenylene|methylene)}
+\end{example}
+
+\paragraph{Hetero Atoms and added Hydrogen}
+
+Attachments to hetero atoms and added hydrogen atoms are indicated by italic
+letters~\cite{iupac:greenbook}. \chemmacros\ defines a few macros for the
+most common ones.
+\begin{commands}
+ \iupaccs[H]{hydrogen}{The italic H for hydrogen.}
+ \iupaccs[O]{oxygen}{The italic O for oxygen.}
+ \iupaccs[N]{nitrogen}{The italic N for nitrogen.}
+ \iupaccs[Sf]{sulfur}{The italic S for sulfur.}
+ \iupaccs[P]{phosphorus}{The italic P for phosphorus.}
+\end{commands}
+\begin{example}[side-by-side]
+ \iupac{\nitrogen-methyl|benz|amide}
+
+ \iupac{3\hydrogen-pyrrole}
+
+ \iupac{\oxygen-ethyl hexanethioate}
+\end{example}
+
+\paragraph{Cahn-Ingold-Prelog}\label{par:cip}
+\begin{commands}
+ \command{cip}[\marg{conf}]
+ Typeset Cahn-Ingol-Prelog descriptors, \eg: \cs{cip}\Marg{R,S}
+ \cip{R,S}. \meta{conf} may be a csv list of entries.
+ \iupaccs[R]{rectus}{The rectus descriptor.}
+ \iupaccs[S]{sinister}{The sinister descriptor.}
+\end{commands}
+
+Both these commands and the entgegen/zusammen descriptors get a small
+additional amount of kerning after the closing parenthesis. This amount can
+be changed through the following option:
+\begin{options}
+ \keyval{cip-kern}{dim}\Module{nomenclature}\Default{.075em}
+ Set the amount of kerning after the closing parenthesis.
+\end{options}
+The entries typeset by and implemented with \cs{cip} can be customized
+further:
+\begin{options}
+ \keyval{cip-outer-format}{format}\Default{\cs*{upshape}}
+ \sinceversion{5.8}The format of parentheses and commas typeset by
+ \cs{cip}.
+ \keyval{cip-inner-format}{format}\Default{\cs*{itshape}}
+ \sinceversion{5.8}The format of the entries in \cs{cip}. This format
+ works additive to the outer format.
+ \keyval{cip-number-format}{format}\Default{\cs*{itshape}}
+ \sinceversion{5.8}The format of numbers in \cs{cip}. This format works
+ additive to the outer format and is applied to arabic figures only.
+\end{options}
+
+\paragraph{Fischer}
+\begin{commands}
+ \iupaccs[D]{dexter}{The dexter descriptor.}
+ \iupaccs[L]{laevus}{The laevus descriptor.}
+\end{commands}
+
+\paragraph{cis/trans, zusammen/entgegen, syn/anti \& tert}
+\begin{itemize}
+ \item \cs{cis} \iupac{\cis} \quad \cs{trans} \iupac{\trans}
+ \item \cs{fac} \iupac{\fac} \quad \cs{mer} \iupac{\mer}
+ \item \cs{sin} \iupac{\sin} \quad \cs{ter} \iupac{\ter}
+ \item \cs{zusammen} \iupac{\zusammen} \quad \cs{entgegen} \iupac{\entgegen}
+ \item \cs{syn} \iupac{\syn} \quad \cs{anti} \iupac{\anti}
+ \item \cs{tert} \iupac{\tert}
+\end{itemize}
+An alias for \cs{entgegen} is \cs{E} and an alias for \cs{zusammen} is
+\cs{Z}.
+
+\paragraph{ortho/meta/para}
+\begin{center}
+ \cs{ortho} \iupac{\ortho} \quad
+ \cs{meta} \iupac{\meta} \quad
+ \cs{para} \iupac{\para}
+\end{center}
+
+Although these commands are provided I like to cite
+\citetitle{iupac:bluebook}~\cite{iupac:bluebook}:
+
+\begin{cnltxquote}[{\cite[][p.\,90]{iupac:bluebook}}]
+ The letters \iupac{\ortho}, \iupac{\meta}, and \iupac{\para} have been used
+ in place of \textit{ortho}, \textit{meta}, and \textit{para}, respectively,
+ to designate the 1,2-, 1,3-, and 1,4- isomers of disubstituted benzene.
+ This usage is strongly discouraged and is not used in preferred \acs{iupac}
+ names.
+\end{cnltxquote}
+
+\paragraph{Absolute Configuration}
+\begin{commands}
+ \command{Rconf}[\oarg{letter}]
+ \cs{Rconf}: \Rconf \quad \cs{Rconf}\oarg{}: \Rconf[]
+ \command{Sconf}[\oarg{letter}]
+ \cs{Sconf}: \Sconf \quad \cs{Sconf}\oarg{}: \Sconf[]
+\end{commands}
+
+\paragraph{Coordination Chemistry}
+
+\chemmacros\ provides a few commands useful in coordination chemistry:
+\begin{commands}
+ \command{bridge}[\marg{num}\quad\bridge{3}]
+ Denote bridging ligand connection.
+ \command{hapto}[\marg{num}\quad\hapto{5}]
+ Denote hapticity.
+ \command{dento}[\marg{num}\quad\dento{2}]
+ Denote denticity.
+\end{commands}
+\begin{example}
+ Ferrocene = \iupac{bis(\hapto{5}cyclo|penta|dienyl)iron} \par
+ \iupac{tetra-\bridge{3}iodido-tetrakis[tri|methyl|platinum(IV)]}
+\end{example}
+
+Two options allow customization:
+\begin{options}
+ \keychoice{bridge-number}{sub,super}\Module{nomenclature}\Default{sub}
+ Appends the number as a subscript or superscript, depending on the choice.
+ The \ac{iupac} recommendation is the subscript~\cite{iupac:redbook}.
+ \keybool{coord-use-hyphen}\Module{nomenclature}\Default{true}
+ Append a hyphen to \cs{hapto}, \cs{dento} and \cs{bridge} or don't.
+\end{options}
+
+The default behaviour\sinceversion{5.8} of \cs{hapto} and \cs{dento} has
+changed with version~5.8 to follow \ac{iupac} recommendations.
+
+\paragraph{Examples}
+\begin{example}
+ \iupac{\dexter-Wein|s\"aure} =
+ \iupac{\cip{2S,3S}-Wein|s\"aure} \par
+ \iupac{\dexter-($-$)-Threose} =
+ \iupac{\cip{2S,3R}-($-$)-2,3,4-Tri|hydroxy|butanal} \par
+ \iupac{\cis-2-Butene} =
+ \iupac{\zusammen-2-Butene}, \par
+ \iupac{\cip{2E,4Z}-Hexa|diene} \par
+ \iupac{\meta-Xylol} =
+ \iupac{1,3-Di|methyl|benzene}
+\end{example}
+
+\subsubsection{Own \cs*{iupac} Macros And Shorthands}
+
+If you find any commands missing you can define them using
+\begin{commands}
+ \command{NewChemIUPAC}[\marg{cs}\marg{declaration}]
+ Define a new \ac{iupac} command that is in any case defined inside of
+ \cs{iupac} regardless if \meta{cs} is defined elsewhere already.
+ \command{ProvideChemIUPAC}[\marg{cs}\marg{declaration}]
+ Define a new \ac{iupac} command that is in any case defined inside of
+ \cs{iupac} regardless if \meta{cs} is defined elsewhere already only if
+ the corresponding \ac{iupac} macro is not defined, yet.
+ \command{RenewChemIUPAC}[\marg{cs}\marg{declaration}]
+ Redefine an existing \ac{iupac} command that is in any case defined inside
+ of \cs{iupac} regardless if \meta{cs} is defined elsewhere already.
+ \command{DeclareChemIUPAC}[\marg{cs}\marg{declaration}]
+ Define a new \ac{iupac} command that is in any case defined inside of
+ \cs{iupac} regardless if \meta{cs} is defined elsewhere already. This
+ silently overwrites an existing \ac{iupac} macro definition.
+ \command{LetChemIUPAC}[\marg{cs1}\marg{cs2}]
+ Defines \meta{cs1} to be an alias of \meta{cs2}.
+\end{commands}
+A command defined in this way will obey the setting of the option
+\option{iupac}. This means any existing command is only overwritten with
+\keyis{iupac}{strict}. However, \cs{NewChemIUPAC} will \emph{not} change the
+definition of an existing \ac{iupac} naming command but issue an error if the
+\ac{iupac} naming command already exists. \cs{DeclareChemIUPAC} \emph{will}
+overwrite an existing \ac{iupac} command.
+\begin{example}
+ \NewChemIUPAC\endo{\textsc{endo}}
+ \RenewChemIUPAC\anti{\textsc{anti}}
+ \iupac{(2-\endo,7-\anti)-2-bromo-7-fluoro|bicyclo[2.2.1]heptane}
+\end{example}
+
+\cs{RenewChemIUPAC} allows you to redefine the existing \ac{iupac} naming
+commands.
+\begin{example}[side-by-side]
+ \iupac{\meta-Xylol} \par
+ \RenewChemIUPAC\meta{\textup{m}}
+ \iupac{\meta-Xylol}
+\end{example}
+
+There's also a way for defining new \ac{iupac} shorthands or changing the
+existing ones:
+\begin{commands}
+ \command{NewChemIUPACShorthand}[\meta{shorthand token}\meta{control sequence}]
+ Defines a new \ac{iupac} shorthand. Inside \cs{iupac} it will be equal to
+ using \meta{control sequence}. This throws an error if \meta{shorthand
+ token} is already defined.
+ \command{RenewChemIUPACShorthand}[\meta{shorthand token}\meta{control sequence}]
+ Redefines an existing \ac{iupac} shorthand. This throws an error if
+ \meta{shorthand token} is not defined, yet.
+ \command{DeclareChemIUPACShorthand}[\meta{shorthand token}\meta{control sequence}]
+ Defines a new \ac{iupac} shorthand or redefines an existing one.
+ \command{ProvideChemIUPACShorthand}[\meta{shorthand token}\meta{control sequence}]
+ Provides a new \ac{iupac} shorthand. Does nothing if \meta{shorthand
+ token} is already defined.
+ \command{RemoveChemIUPACShorthand}[\meta{shorthand token}]
+ Deletes an existing \ac{iupac} shorthand.
+\end{commands}
+
+\subsubsection{Latin Phrases}
+
+\chemmacros\ provides a command for typesetting latin phrases:
+\begin{commands}
+ \command{latin}[\oarg{options}\marg{phrase}]
+ Typesets \meta{phrase} according to the option \option{format} described
+ below.
+ \command{insitu}[\quad\insitu]
+ \command{invacuo}[\quad\invacuo]
+ \command{abinitio}[\quad\abinitio]
+\end{commands}
+
+If you additionally load \pkg{chemstyle}~\cite{pkg:chemstyle} said package
+will \emph{not} define its own \cs{latin}.
+
+% The package \pkg{chemstyle}~\cite{pkg:chemstyle} provides the command
+% \cs{latin} to typeset common latin phrases in a consistent way. \chemmacros\
+% defines a similar \cs{latin} only if \pkg{chemstyle} has \emph{not} been
+% loaded and additionally provides these commands:
+% \begin{center}
+% \cs{insitu} \insitu \quad
+% \cs{abinitio} \abinitio \quad
+% \cs{invacuo} \invacuo
+% \end{center}
+
+% \emph{If the package \pkg{chemstyle} has been loaded they are defined using
+% \pkg{chemstyle}'s \cs{latin} command. This means that then the appearance
+% depends on \pkg{chemstyle}'s option \code{abbremph}.}
+
+The last three commands mentioned above are defined through
+\begin{commands}
+ \command{NewChemLatin}[\marg{cs}\marg{phrase}]
+ Define a new latin phrase. Gives an error if \meta{cs} already exists.
+ \command{DeclareChemLatin}[\marg{cs}\marg{phrase}]
+ Define a new latin phrase. Silently redefined existing macros.
+ \command{RenewChemLatin}[\marg{cs}\marg{phrase}]
+ Redefine an existing latin phrase. Gives an error if \meta{cs} doesn't
+ exist.
+ \command{ProvideChemLatin}[\marg{cs}\marg{phrase}]
+ Define a new latin phrase only if \meta{cs} doesn't exist.
+\end{commands}
+\begin{example}[side-by-side]
+ \NewChemLatin\ltn{latin text}\ltn
+\end{example}
+You can change the appearance with this option:
+\begin{options}
+ \keyval{format}{definition}\Module{nomenclature}\Default{\cs*{emph}}
+ \changedversion{5.7}Sets the format for the latin phrases.
+\end{options}
+
+\subsection{The \chemmodule*{particles} Module}\label{sec:particles-module}
+
+The \chemmodule{particles} module loads the modules \chemmodule{charges} and
+\chemmodule{chemformula}.
+
+\subsubsection{Provided Particle Macros}
+The \chemmodule{particles} defines a number of macros which can be used for
+typesetting common particles in the running text. Most of them don't make
+much sense in \pkg{chemformula}~\cite{pkg:chemformula}'s \cs{ch}, though,
+which doesn't mean that they can't be used there, of course:
+\begin{center}
+ \cs{el} \el\ \cs{prt} \prt\ \cs{ntr} \ntr\ \cs{Hyd} \Hyd\ \cs{Oxo} \Oxo\
+ \cs{water} \water\ \cs{El} \El\ \cs{Nuc} \Nuc\ \cs{ba} \ba
+\end{center}
+All of these macros are defined using \pkg{chemformula}'s \cs{chcpd}. The
+details are explained in section~\vref{sec:defin-own-part}.
+
+The macros \cs{Nuc} and \cs{ba} are special: they have an optional argument
+for the following options:
+\begin{options}
+ \keychoice{elpair}{dots,dash,false}\Module{particles}\Default{false}
+ Determine how the electron pair of the nucleophiles is displayed. The
+ electron pair is drawn using \chemformula's \cs{chlewis} macro.
+ \keyval{space}{dim}\Module{particles}\Default{.1em}
+ Sets\sinceversion{5.3} the space that is inserted between the electron
+ pair and the negative charge sign.
+\end{options}
+Both options can of course also be set with \cs{chemsetup}.
+
+\begin{example}[side-by-side]
+ \ba[elpair=dots] \Nuc[elpair=dash]
+
+ \chemsetup[particles]{elpair=false}
+ \ba\ \Nuc
+\end{example}
+
+\subsubsection{Defining Own Particle Macros}\label{sec:defin-own-part}
+
+There are two sets of macros, one for defining particles and one for defining
+nucleophiles.
+\begin{commands}
+ \command{NewChemParticle}[\marg{cs}\marg{formula}]
+ Defines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ input (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Raises an error if \meta{cs} already
+ exists.
+ \command{RenewChemParticle}[\marg{cs}\marg{formula}]
+ Redefines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ input (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Raises an error if \meta{cs} doesn't
+ exist.
+ \command{DeclareChemParticle}[\marg{cs}\marg{formula}]
+ Defines a macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ input (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Silently overwrites \meta{cs} if it
+ exists.
+ \command{ProvideChemParticle}[\marg{cs}\marg{formula}]
+ Defines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ input (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Does nothing if \meta{cs} already
+ exists.
+\end{commands}
+An example of usage is the definition of the existing particle macros:
+\begin{sourcecode}
+ \NewChemParticle\el {e-}
+ \NewChemParticle\prt{p+}
+ \NewChemParticle\ntr{n^0}
+\end{sourcecode}
+
+The following set defines macros like \cs{Nuc}
+\begin{commands}
+ \command{NewChemNucleophile}[\marg{cs}\marg{formula}]
+ Defines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ input (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Note that \meta{formula} will get a
+ trailing negative charge! Raises an error if \meta{cs} already exists.
+ \command{RenewChemNucleophile}[\marg{cs}\marg{formula}]
+ Redefines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Note that \meta{formula} will get a
+ trailing negative charge! Raises an error if \meta{cs} doesn't exist.
+ \command{DeclareChemNucleophile}[\marg{cs}\marg{formula}]
+ Defines a macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Note that \meta{formula} will get a
+ trailing negative charge! Silently overwrites \meta{cs} if it exists.
+ \command{ProvideChemNucleophile}[\marg{cs}\marg{formula}]
+ Defines a new macro \meta{cs}. \meta{formula} is any valid \chemformula\
+ (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}). Note that \meta{formula} will get a
+ trailing negative charge! Does nothing if \meta{cs} already exists.
+\end{commands}
+An example of usage is the definition of the existing nucleophile macros:
+\begin{sourcecode}
+ \NewChemNucleophile\Nuc{Nu}
+ \NewChemNucleophile\ba {ba}
+\end{sourcecode}
+A macro defined this way will have an optional argument for the
+\option{elpair} option.
+
+\subsection{The \chemmodule*{phases} Module}\label{sec:phases-module}
+
+The \chemmodule{phases} module loads the \chemmodule{chemformula} modul.
+
+\subsubsection{Basics}
+
+These commands are intended to indicate the phase of a compound.
+\begin{center}
+ \cs{sld} \sld \quad \cs{lqd} \lqd \quad \cs{gas} \gas \quad \cs{aq} \aq
+\end{center}
+\begin{example}
+ \ch{C\sld{} + 2 H2O\lqd{} -> CO2\gas{} + 2 H2\gas}\par
+ To make it complete: NaCl\aq.
+\end{example}
+
+The \ac{iupac} recommendation to indicate the state of aggregation is to put
+it in parentheses after the compound \cite{iupac:greenbook}. However, you
+might want to put it as a subscript which is also very common.
+
+\begin{cnltxquote}[{\citetitle{iupac:greenbook}~\cite[][p.\,54]{iupac:greenbook}}]
+ The \textelp{} symbols are used to represent the states of aggregation of
+ chemical species. The letters are appended to the formula in parentheses
+ and should be printed in Roman (upright) type without a full stop (period).
+\end{cnltxquote}
+
+There are two options to customize the output:
+\begin{options}
+ \keychoice{pos}{side,sub}\Module{phases}\Default{side}
+ Switch the position of the phase indicator.
+ \keyval{space}{dim}\Module{phases}\Default{.1333em}
+ Change the default spacing between compound a phase indicator if
+ \keyis{pos}{side}. A \TeX\ dimension.
+\end{options}
+\begin{example}
+ \chemsetup[phases]{pos=sub}
+ \ch{C\sld{} + 2 H2O\lqd{} -> CO2\gas{} + 2 H2\gas}\par
+ To make it complete: NaCl\aq.
+\end{example}
+
+All those phase commands have an optional argument:
+\begin{example}[side-by-side]
+ \ch{H2O "\lqd[\SI{5}{\celsius}]"}
+\end{example}
+
+There is also a generic phase command:
+\begin{commands}
+ \command{phase}[\marg{phase}]
+ If you need a phase indicator just once or twice. You can use it to
+ denote a phase for which there is no phase command, yet.
+\end{commands}
+
+\subsubsection{Define Own Phases}
+Depending on the subject of your document you might need to indicate other
+states of aggregation. You can easily define them.
+\begin{commands}
+ \command{NewChemPhase}[\marg{cs}\marg{symbol}]
+ Define a new phase command. See section~\vref{sec:lang-depend} for a way
+ to define language dependent settings. Gives an error if \meta{cs}
+ already exists.
+ \command{DeclareChemPhase}[\marg{cs}\marg{symbol}]
+ Define a new phase command. See section~\vref{sec:lang-depend} for a way to
+ define language dependent settings. Overwrites previous definitions of
+ \meta{cs}.
+ \command{RenewChemPhase}[\marg{cs}\marg{symbol}]
+ Redefine an existing phase command. See section~\vref{sec:lang-depend} for
+ a way to define language dependent settings. Gives an error if \meta{cs}
+ is not defined.
+ \command{ProvideChemPhase}[\marg{cs}\marg{symbol}]
+ Define a new phase command. See section~\vref{sec:lang-depend} for a way
+ to define language dependent settings. Does nothing if \meta{cs} is
+ already defined.
+\end{commands}
+
+\begin{example}
+ % preamble:
+ \NewChemPhase\aqi{aq,$\infty$} % aqueous solution at infinite dilution
+ \NewChemPhase\cd {cd} % condensed phase
+ \NewChemPhase\lc {lc} % liquid crystal
+ \ch{NaOH\aqi} \ch{H2O\cd} \ch{U\phase{cr}} \ch{A\lc}\par
+ \chemsetup[phases]{pos=sub}
+ \ch{NaOH\aqi} \ch{H2O\cd} \ch{U\phase{cr}} \ch{A\lc}
+\end{example}
+
+\subsubsection{Language Dependencies}\label{sec:lang-depend}
+For each phase command a translation into the custom language can be defined.
+If a phase is declared with \cs{NewChemPhase} no translation exists and
+for every \pkg{babel} language the literal string is used that was provided
+as a definition. Let's say you define the phase
+\begin{sourcecode}
+ \NewChemPhase\liquid{l}
+\end{sourcecode}
+and want to add the German translation ``f\/l''. Then you could do
+\begin{sourcecode}
+ \DeclareTranslation{German}{phase-liquid}{f\/l}
+\end{sourcecode}
+This way, when you use it in a German document using the appropriate
+\pkg{babel} option using \cs*{liquid} would correctly translate. For this the
+package \pkg{translations}~\cite{pkg:translations} is used. The \acs{id}
+always is \code{phase-\meta{csname}} where \meta{csname} is the name of the
+phase command you defined without leading backslash.
+
+See section~\vref{sec:lang-module} for predefined translations and general
+language options of \chemmacros.
+
+\subsection{The \chemmodule*{symbols} Module}\label{sec:symbols-module}
+
+The \chemmodule{symbols} module defines a few symbols chemists need now and
+then. It loads the package \pkg{amstext}~\cite{pkg:amstext}.
+\begin{commands}
+ \command{transitionstatesymbol}
+ This is self-explaining: \transitionstatesymbol
+ \command{standardstate}
+ Again self-explaining: \standardstate
+ \command{changestate}
+ The uppercase delta used in \state[superscript=]{H} for example.
+\end{commands}
+
+\section{Internal Modules}
+\subsection{The \chemmodule*{base} Module}\label{sec:base-module}
+
+The \chemmodule{base} module is the core module of \chemmacros. It defines
+some tools which can (and should) be used in other modules. This means this
+section is only interesting for you if you plan to write a module yourself
+(see section~\vref{sec:own-modules} for details).
+
+This module requires the packages \pkg{bm}~\cite{pkg:bm},
+\pkg{amstext}~\cite{pkg:amstext}, and \pkg{etoolbox}~\cite{pkg:etoolbox}.
+
+This module also provides \cs{chemsetup} and the option \option{modules}.
+
+It also provides a number of (expl3) macros which may be used in other
+modules. In the macro descriptions below \TF\ denotes that a \code{T}, an
+\code{F} and a \code{TF} variant exist. In case of an expandable conditional
+(\expandablesymbol) also the predicate variant is available.
+\begin{commands}
+ \expandable\explcommand{chemmacros_if_loaded:nn}[\TF\
+ \Marg{package|class} \marg{name} \marg{true} \marg{false}]
+ Checks if package (or class) \meta{name} has been loaded. Also works after
+ begin document.
+ \expandable\explcommand{chemmacros_if_package_loaded:n}[\TF\ \marg{name}
+ \marg{true} \marg{false}]
+ Checks if package \meta{name} has been loaded. Also works after begin
+ document.
+ \expandable\explcommand{chemmacros_if_class_loaded:n}[\TF\ \marg{name}
+ \marg{true} \marg{false}]
+ Checks if class \meta{name} has been loaded. Also works after begin
+ document.
+ \explcommand{chemmacros_leave_vmode:}
+ Equivalent of \cs*{leavevmode}.
+ \explcommand{chemmacros_nobreak:}
+ Inserts a penalty of \num{10000}.
+ \explcommand{chemmacros_allow_break:}
+ Inserts a penalty of \num{0}.
+ \explcommand{chemmacros_skip_nobreak:N}[ \meta{skip/length variable}]
+ Insert a horizontal skip where a linebreak is disallowed.
+ \expandable\explcommand{chemmacros_if_is_int:n}[\TF\ \marg{input} \marg{true}
+ \marg{false}]
+ Checks if \meta{input} is an integer or something else.
+ \explcommand{chemmacros_if_bold:}[\TF\ \marg{true} \marg{false}]
+ Checks if the current font weight is one of \chemboldchecks{or}.
+ \explcommand{chemmacros_bold:n}[ \marg{text}]
+ Checks if the current font weight is bold and if yes places \meta{text} in
+ \cs*{textbf} if in text mode or in \cs*{bm} if in math mode. If no
+ \meta{text} simply is placed in the input stream as is.
+ \explcommand{chemmacros_text:n}[ \marg{text}]
+ Ensures that \meta{text} is placed in text mode.
+ \explcommand{chemmacros_math:n}[ \marg{text}]
+ Ensures that \meta{text} is placed in math mode.
+ \explcommand{chemmacros_new_macroset:nnn}[ \marg{name} \marg{arg spec}
+ \marg{internal command call}]
+ \changedversion{5.3b}A command to define a set of macros
+ \cs*{NewChem\meta{name}}, \cs*{RenewChem\meta{name}},
+ \cs*{DeclareChem\meta{name}} and \cs*{ProvideChem\meta{name}} where the
+ first letter of \meta{name} is converted to uppercase, other letters are
+ kept unchanged. \meta{arg spec} is any valid argument specification for
+ \pkg{xparse}'s \\
+ \cs{DeclareDocumentCommand}~\cite{bnd:l3packages}. \meta{internal command
+ call} should be a macro which makes definitions \emph{without} error
+ checks, \ie, define new macros or redefine existing ones like \cs*{def}
+ does. This macro just should get the arguments passed on to. Have a look
+ at the example below.
+ \explcommand{chemmacros_new_environment_macroset:nnn}[ \marg{name} \marg{arg spec}
+ \marg{internal command call}]
+ Like \explcs{chemmacros_new_macroset:nnn} but for environments.
+ \command{NewChemMacroset}[\sarg\marg{name}\marg{arg spec}\marg{internal
+ command call}]
+ A non-expl3 version of \explcs{chemmacros_new_macroset:nnn} for \LaTeXe\
+ programmers. The starred version calls
+ \explcs{chemmacros_new_environment_macroset:nnn}.
+ \explcommand{chemmacros_add_cleveref_support:nnnnn}[ \marg{counter}
+ \marg{singular} \marg{plural} \marg{uppercase singular} \marg{uppercase
+ plural}]
+ A\sinceversion{5.6} command to add suiting names for a counter for the
+ \pkg{cleveref} package's \cs*{cref} commands. This command acts at the
+ end of the preamble and only if a user hasn't provided definitions with
+ \cs*{crefname} already.
+ \command{ChemCleverefSupport}[\marg{counter}\marg{singular}\oarg{uppercase
+ singular}\marg{plural}\oarg{uppercase plural}]
+ \sinceversion{5.6}\LaTeXe-version of
+ \explcs{chemmacros_add_cleveref_support:nnnnn}.
+ \explcommand{chemmacros_add_fancyref_support:nnn}[ \marg{prefix} \marg{name}
+ \marg{uppercase name}]
+ A\sinceversion{5.6} command to add suiting names for a counter for the
+ \pkg{fancyref} package's \cs*{fref} commands. This command acts at the
+ end of the preamble and doesn't override definitions made by the users.
+ \command{ChemFancyrefSupport}[\marg{prefix}\marg{name}\oarg{uppercase name}]
+ \sinceversion{5.6}\LaTeXe-version of
+ \explcs{chemmacros_add_fancyref_support:nnnnn}.
+\end{commands}
+This is how the macros \cs{NewChemParticle}, \cs{RenewChemParticle},
+\cs{DeclareChemParticle} and \cs{ProvideChemParticle} were defined:
+\begin{sourcecode}
+ \NewChemMacroset {Particle} {mm}
+ { \chemmacros_define_particle:Nn #1 {#2} }
+\end{sourcecode}
+
+The following macros strictly speaking are not provided by the
+\chemmodule{base} module but this place fits best for their description.
+\begin{commands}
+ \expandable\explcommand{chemmacros_if_module_exist:n}[\TF\ \marg{module}
+ \marg{true} \marg{false}]
+ Checks if a file with the correct name for a module \meta{module} can be
+ found.
+ \expandable\explcommand{chemmacros_if_module_loaded:n}[\TF\ \marg{module}
+ \marg{true} \marg{false}]
+ Checks if the module \meta{module} has already been loaded or not.
+ \explcommand{chemmacros_load_module:n}[ \marg{module}]
+ Loads module \meta{module} if it hasn't been loaded, yet.
+ \explcommand{chemmacros_load_modules:n}[ \marg{csv list of modules}]
+ Loads every module in \meta{csv list of modules} if they haven't been
+ loaded, yet. This is the code level variant of \cs{usechemmodule}.
+ \explcommand{chemmacros_before_module:nn}[ \marg{module} \marg{code}]
+ Saves\sinceversion{5.1} \meta{code} and inserts it right before
+ \meta{module} is loaded. If \meta{module} is never loaded then
+ \meta{code} is never inserted. If \meta{module} already is loaded when
+ the command is used then \meta{code} also is never inserted.
+ \explcommand{chemmacros_after_module:nn}[ \marg{module} \marg{code}]
+ Saves\sinceversion{5.1} \meta{code} and inserts it right after
+ \meta{module} is loaded. If \meta{module} is never loaded then
+ \meta{code} is never inserted. If \meta{module} already is loaded when
+ the command is used then \meta{code} is inserted immediately.
+\end{commands}
+
+\subsection{The \chemmodule*{chemformula} Module}\label{sec:chemformula-module}
+
+The \chemmodule{chemformula} module loads the \pkg{amstext}
+package~\cite{pkg:amstext} and the \chemmodule{charges} module.
+
+\subsubsection{For Users}
+There are different packages which provide means for typesetting chemical
+formulas:
+\begin{itemize}
+ \item \pkg{chemformula}~\cite{pkg:chemformula}. This is probably well known
+ to users of \chemmacros.
+ \item \pkg{mhchem}~\cite{pkg:mhchem}. This is the \enquote{older brother} of
+ \chemformula.
+ \item \pkg{chemfig}~\cite{pkg:chemfig}. The easiest and most complete of the
+ packages for drawing skeletal formulas.
+ \item \XyMTeX~\cite{pkg:xymtex}. A very comprehensive alternative for
+ typesetting chemistry.
+\end{itemize}
+In order to help authors getting a consistent layout \chemmacros\ does not
+make a choice which package to use for typesetting formulas. Although
+\chemformula\ is well tested and preferred users can choose other packages if
+they like.
+
+this is done with the following general option:
+\begin{options}
+ \keyval{formula}{method}\Default{chemformula}
+ This\sinceversion{5.1} option let's you choose how chemical formulas are
+ typeset. Available methods are
+ \begin{itemize}
+ \item \pkg{chemformula}
+ \item \pkg{mhchem}
+ \item \pkg{chemist}\sinceversion{5.6} (from the \XyMTeX\ bundle)
+ \item \pkg{chemfig}\sinceversion{5.6}
+ \end{itemize}
+ The corresponding package with the same name is loaded.
+\end{options}
+If you explicitly set this option the corresponding package is loaded
+immediately and the method is set up. Otherwise the option will be set by
+\chemmacros\ at the end of the preamble.
+
+If\sinceversion{5.2} you load a method package in a way that a unique choice
+is possible then \chemmacros\ will set the method accordingly if you haven't
+set the option by yourself. If \emph{no} unique choice is possible
+\chemmacros\ will raise a warning and choose \pkg{chemformula} regardless if
+the package is loaded or not. In this case if you want to use another method
+you'll have to choose manually. \emph{All automatic choices only happen at the
+ end of the preamble}.
+
+\paragraph{Using the \pkg*{chemformula} Package}
+If you set \keyis{formula}{chemformula} the \chemmodule{chemformula} module
+makes it possible that you can set all \chemformula\ options via the
+\cs{chemsetup} command using the module \module{chemformula}, for example:
+\begin{sourcecode}
+ \chemsetup[chemformula]{format=\sffamily}
+\end{sourcecode}
+
+Everywhere where \chemmacros\ typesets chemical formulas \chemformula's macros
+\cs{chcpd} or \cs{ch} are used, for example in the reaction environments
+provided by the \chemmodule{reactions} module.
+
+\emph{This method is the recommended choice!}
+
+\paragraph{Using the \pkg*{mhchem} Package}\sinceversion{5.1}\label{sec:using-mhchem}
+If you set \keyis{formula}{mhchem} the \chemmodule{chemformula} module makes
+it possible that you can set all of \pkg{mhchem}'s options via the
+\cs{chemsetup} command using the module \module{mhchem}, for example:
+\begin{sourcecode}
+ \chemsetup[mhchem]{format=\sffamily}
+\end{sourcecode}
+
+Everywhere where \chemmacros\ typesets chemical formulas \pkg{mhchem}'s macro
+\cs{ce} is used, for example in the reaction environments provided by the
+\chemmodule{reactions} module.
+
+There are some \latin{caveat}s if you use this method:
+\begin{itemize}
+ \item This method has not been extensively tested, yet. There may be errors
+ and wrong output at unexpected places.
+ \item Using this method effectively disables the different values of the
+ \module{particles} option \option{elpair} (see
+ section~\ref{sec:particles-module}).
+ \item The different kinds of formal charges provided by the
+ \chemmodule{charges} module (see section~\ref{sec:ion-charges}) are
+ disabled. Formal charges always use the math method now.
+ \item There may also be other incompatibilities (\eg, \pkg{mhchem} has it's
+ own method of setting upright Greek letters so it may or may not disable
+ \chemmacros' mechanism).
+\end{itemize}
+
+\paragraph{Using the \pkg*{chemfig} Package}\sinceversion{5.6}\label{sec:using-chemfig}
+Everywhere where \chemmacros\ typesets chemical formulas \pkg{chemfig}'s macro
+\cs{printatom} is used, for example in the reaction environments provided by
+the \chemmodule{reactions} module.
+
+There are some \latin{caveat}s if you use this method:
+\begin{itemize}
+ \item This method has not been extensively tested, yet. There may be errors
+ and wrong output at unexpected places.
+ \item Using this method effectively disables the different values of the
+ \module{particles} option \option{elpair} (see
+ section~\ref{sec:particles-module}).
+ \item The different kinds of formal charges provided by the
+ \chemmodule{charges} module (see section~\ref{sec:ion-charges}) are
+ disabled. Formal charges always use the math method now.
+ \item The reaction environments by the \chemmodule{reactions} module may
+ work only to a limited respect. If you plan to use them consider using
+ methods \pkg{chemformula} or \pkg{mhchem} instead.
+\end{itemize}
+
+\paragraph{Using the \pkg*{chemist} Package}\sinceversion{5.6}\label{sec:using-chemist}
+Everywhere where \chemmacros\ typesets chemical formulas \pkg{chemist}'s macro
+\cs{ChemForm} is used, for example in the reaction environments provided by
+the \chemmodule{reactions} module.
+
+There are some \latin{caveat}s if you use this method:
+\begin{itemize}
+ \item This method has not been extensively tested, yet. There may be errors
+ and wrong output at unexpected places.
+ \item Using this method effectively disables the different values of the
+ \module{particles} option \option{elpair} (see
+ section~\ref{sec:particles-module}).
+ \item The different kinds of formal charges provided by the
+ \chemmodule{charges} module (see section~\ref{sec:ion-charges}) are
+ disabled. Formal charges always use the math method now.
+ \item The reaction environments by the \chemmodule{reactions} module may
+ work only to a limited respect. If you plan to use them consider using
+ methods \pkg{chemformula} or \pkg{mhchem} instead\footnote{On the other
+ hand \XyMTeX\ (and especially the \pkg{chemist} package) provides quite
+ a number of chemical reaction environments itself.}.
+\end{itemize}
+
+\subsubsection{For Module Writers}
+
+There are two macros for module writers:
+\begin{commands}
+ \explcommand{chemmacros_chemformula:n}[ \marg{formula}]
+ This is only a wrapper for \cs{chcpd} or \cs{ce}. It is recommended that
+ module writers use this macro (or a variant thereof) inside of
+ \chemmacros' macros whenever they want to display a chemical formula.
+ Writers who prefer traditional \LaTeXe\ programming over expl3 should use
+ \cs*{chemmacros@formula}.
+ \explcommand{chemmacros_reaction:n}[ \marg{reaction}]
+ This is only a wrapper for \cs{ch} or \cs{ce}. It is recommended that
+ module writers use this macro (or a variant thereof) inside of
+ \chemmacros' macros whenever they want to display a chemical reaction.
+ Writers who prefer traditional \LaTeXe\ programming over expl3 should use
+ \cs*{chemmacros@reaction}.
+\end{commands}
+
+\subsection{The \chemmodule*{errorcheck} Module}\label{sec:errorcheck-module}
+The\sinceversion{5.2} \chemmodule{errorcheck} module provides some rudimentary
+support for giving users more meaningful messages when they use a command or
+environment provided by a module that they haven't loaded.
+
+\subsection{The \chemmodule*{greek} Module}\label{sec:greek-module}
+
+The \chemmodule{greek} module loads the \pkg{chemgreek}
+package~\cite{pkg:chemgreek}.
+
+This module provides one option:
+\begin{options}
+ \keyval{greek}{mapping}
+ A valid value is any valid \chemgreek\ \meta{mapping}. \chemmacros\ will
+ warn you if no mapping has been chosen or if you are using the
+ \code{default} or the \code{var-default} mapping because this means that
+ no upright Greek letters are available.
+\end{options}
+If you load a \chemgreek\ support package which allows an unambiguous choice
+of a mapping \chemgreek\ will make this choice automatically. This means if
+you say
+\begin{sourcecode}
+ \usepackage{upgreek}
+ \usepackage{chemmacros}
+\end{sourcecode}
+then \chemmacros\ will use \pkg{upgreek}'s upright Greek letters. If you
+have
+\begin{sourcecode}
+ \usepackage{upgreek}
+ \usepackage{chemmacros}
+ \usepackage{textgreek}
+\end{sourcecode}
+then no unambiguous choice is possible and you should choose a mapping
+yourself, for example:
+\begin{sourcecode}
+ \usepackage{upgreek}
+ \usepackage{chemmacros}
+ \usepackage{textgreek}
+ \chemsetup{greek=textgreek}
+\end{sourcecode}
+For further details on mappings please refer to \chemgreek's manual.
+
+\subsection{The \chemmodule*{lang} Module}\label{sec:lang-module}
+
+The \chemmodule{lang} module provides language support for \chemmacros. It
+loads the package \pkg{translations}~\cite{pkg:translations}.
+
+\subsubsection{Information For Users}\label{sec:information-users}
+
+This module defines the following option:
+\begin{options}
+ \keychoice{language}{auto,\meta{language}}\Default{auto}
+ If set to \code{auto} \chemmacros\ will detect the language used by
+ \pkg{babel}~\cite{pkg:babel} or \pkg{polyglossia}~\cite{pkg:polyglossia}
+ automatically, the fallback translation is English and will be used if no
+ translation for the actual language is available. Any language known to
+ the \pkg{translations} package is a valid value for \meta{language}.
+\end{options}
+
+The language chosen via \option{language} is used for translation of certain
+strings in different places all over \chemmacros. They are mentioned in the
+places when the corresponding function of \chemmacros\ is explained.
+
+Translation is done with the help of the \pkg{translations} package, available
+translation keys are listed in section~\vref{sec:avail-transl-keys}.
+
+\subsubsection{Available Translation Keys}\label{sec:avail-transl-keys}
+
+Table~\vref{tab:translation-keys} lists all predefined translations of the
+available keys. \emph{Some of the translations have changed in
+ version~5.6\changedversion{5.6}.} The \chemmodule{lang} module doesn't
+provide the translations themselves -- they are provided by the corresponding
+modules. A translation key is a unique string\footnote{That is, a string
+ using the definition for strings used for expl3, i.e., converted to a series
+ of category code~12 characters..} of characters. Each key is used to
+identify a replacement text which depends on the current language or the
+language set through the \option{language} option. For each key at least the
+English fallback translation is provided, for most also the German translation
+is provided. For a few keys also other translations are provided. If you
+find that a translation for your language is missing you can provide it in the
+preamble:
+\begin{commands}
+ % \command{DeclareTranslation}[\marg{language}\marg{key}\marg{translation}]
+ % Defines a translation of key \meta{key} for the language \meta{language}.
+ % No error will be raised if a translation of \meta{key} already exists.
+ % This command can only be used in the preamble and is defined by the
+ % \pkg{translations} package.
+ \command{DeclareChemTranslation}[\marg{language}\marg{key}\marg{translation}]
+ \sinceversion{5.6}A command which makes an abstraction from the
+ \pkg{translations} package. It should be used in documents for adding
+ missing translations that are needed. This command can only be used in
+ the preamble.
+ \command{DeclareChemTranslations}[\marg{key}\Marg{\meta{language} =
+ \meta{translation}}]
+ \sinceversion{5.6}A command rather meant for module writers but can be
+ used by document authors as well, of course. It gets a csv list of
+ key\slash value pairs of translations. This command can only be used in
+ the preamble.
+\end{commands}
+If you send me an email (see section~\vref{sec:sugg-bug-reports}) with the
+translations for your language I'll gladly add them to the next release of
+\chemmacros!
+
+\emph{Please do not use \pkg{translations}' \cs{DeclareTranslation} for
+ declaring translations.}
+
+\ForAllChemTranslationsDo{
+ \appto\chemtranslationtable{\texttt{#1} & #2 & \texttt{\detokenize{#3}} \\}
+}
+
+\begin{longtable}{lll}
+ \caption{Translation keys predefined by \chemmacros\ (except
+ \code{phase-aqi}, \code{phase-cd} and \code{phase-lc} which were defined
+ in this document).}
+ \label{tab:translation-keys} \\
+ \toprule
+ \bfseries key & \bfseries language & \bfseries translation \\
+ \midrule
+ \endfirsthead
+ \toprule
+ \bfseries key & \bfseries language & \bfseries translation \\
+ \midrule
+ \endhead
+ \bottomrule
+ \endlastfoot
+ \midrule
+ & & \hfill\emph{continues} \\
+ \endfoot
+ \chemtranslationtable
+\end{longtable}
+
+\subsubsection{Information For Module Writers}
+
+In addition to the commands from section~\vref{sec:avail-transl-keys} the
+following macros are available:
+\begin{commands}
+ \expandable\explcommand{chemmacros_translate:n}[ \marg{translation key}]
+ Translates the given key to the language which is detected automatically
+ or given by the user. Should be used in \chemmacros' macros instead of
+ \pkg{translations}' \cs*{GetTranslation}.
+ \explcommand{l_chemmacros_language_tl}
+ A token list variable that holds the language which is used by
+ \explcs{chemmacros_translate:n} for translation, \emph{after begin
+ document}.
+ \command{ChemTranslate}[\marg{translation key}]
+ A version of \explcs{chemmacros_translate:n} for those who prefer
+ traditional \LaTeXe\ programming over expl3.
+ \explcommand{chemmacros_declare_translation:nnn}[\marg{language}\marg{key}%
+ \marg{translation}]
+ The expl3 version of \cs{DeclareChemTranslation}.
+ \explcommand{chemmacros_declare_translations:nn}[\marg{key}\Marg{\meta{language}
+ = \meta{translation}}]
+ The expl3 version of \cs{DeclareChemTranslations}.
+\end{commands}
+
+\clearpage
+
+\part{Additional Modules}\label{part:additional-modules}
+
+\section{User Modules}
+\subsection{The \chemmodule*{all} \emph{pseudo}-module}\label{sec:all-module}
+
+The \chemmodule{all} module is a pseudo module: it doesn't define any
+functionality at all. It does however load all other modules. So you can say
+\begin{sourcecode}
+ \chemsetup{ modules = all }
+\end{sourcecode}
+to ensure that every module is available. This \emph{will not} load personal
+modules!
+
+\subsection{The \chemmodule*{isotopes} Module}\label{sec:isotopes-module}
+
+The \chemmodule{isotope} module loads the \pkg{elements}
+package~\cite{pkg:elements}. This module defines one user command:
+\begin{commands}
+ \command{isotope}[\sarg\marg{input}]
+ \meta{input} can either be the \emph{symbol} of an element or the
+ \emph{name} of an element. Be aware that \emph{the name is language
+ dependent}, refer to the manual of the \pkg{elements} package for
+ details. To be on the safe side use the element symbol.
+
+ \meta{input} can also be comma separated list:
+ \cs{isotope}\Marg{\meta{nuc},\meta{symbol}}. If you leave \meta{nuc} out
+ then \cs{isotope} will display the most common isotope. Otherwise
+ \meta{nuc} will be used. If \meta{nuc} is an isotope unknown to the
+ \pkg{elements} package \cs{isotope} will write a warning to the log file.
+
+ The starred variant omits the element number.
+\end{commands}
+
+\begin{example}[side-by-side]
+ \isotope{C}
+ \isotope*{C}
+ \isotope{14,C}
+ \isotope*{14,C}
+\end{example}
+
+As input for the element symbol you can choose any of the elements known to
+the \pkg{elements} package.
+
+There are options which allow you to determine how the isotope is printed:
+\begin{options}
+ \keychoice{format}{super,side}\Module{isotopes}\Default{super}
+ Either print the isotope number as superscript or to the right of the
+ element symbol.
+ \keyval{side-connect}{input}\Module{isotopes}\Default{-}
+ Determine what is printed between the element symbol and the isotope
+ number if \keyis{format}{side}.
+\end{options}
+
+\begin{example}[side-by-side]
+ \isotope{C}
+ \chemsetup[isotopes]{format=side}
+ \isotope{C}
+ \chemsetup[isotopes]{side-connect=}
+ \isotope{C}
+\end{example}
+
+\subsection{The \chemmodule*{mechanisms} Module}\label{sec:mechanisms-module}
+
+The module \chemmodule{mechanisms} loads the package
+\pkg{amstext}~\cite{pkg:amstext}. It provides one macro:
+
+\begin{commands}
+ \command{mech}[\oarg{type}]
+ Allows to specify the most common reaction mechanisms.
+\end{commands}
+\meta{type} can have one of the following values:
+\begin{commands}
+ \command{mech}
+ (empty, no opt. argument) nucleophilic substitution \mech
+ \command{mech}[\Oarg{1}]
+ unimolecular nucleophilic substitution \mech[1]
+ \command{mech}[\Oarg{2}]
+ bimolecular nucleophilic substitution \mech[2]
+ \command{mech}[\Oarg{se}]
+ electrophilic substitution \mech[se]
+ \command{mech}[\Oarg{1e}]
+ unimolecular electrophilic substitution \mech[1e]
+ \command{mech}[\Oarg{2e}]
+ bimolecular electrophilic substitution \mech[2e]
+ \command{mech}[\Oarg{ar}]
+ electrophilic aromatic substitution \mech[ar]
+ \command{mech}[\Oarg{e}]
+ elimination \mech[e]
+ \command{mech}[\Oarg{e1}]
+ unimolecular elimination \mech[e1]
+ \command{mech}[\Oarg{e2}]
+ bimolecular elimination \mech[e2]
+ \command{mech}[\Oarg{cb}]
+ unimolecular elimination \enquote{conjugated base}, \ie, via carbanion
+ \mech[cb]
+\end{commands}
+
+\subsection{The \chemmodule*{newman} Module}\label{sec:newman-module}
+The \chemmodule{newman} module provides a command for drawing Newman
+projections. It loads the \chemmodule{tikz} module.
+\begin{commands}
+ \command{newman}[\oarg{options}\darg{angle}%
+ \Marg{\meta{1},\meta{2},\meta{3},\meta{4},\meta{5},\meta{6}}]
+ Create Newman projections. This command uses \TikZ\ internally.
+ \meta{angle} rotates the back atoms counter clockwise with respect to the
+ front atoms and is an optional argument. \meta{1} to \meta{6} are the
+ positions, the first three are the front atoms, the last three the back
+ atoms.
+\end{commands}
+
+\begin{example}
+ \newman{} \newman(170){}
+ \newman{1,2,3,4,5,6} \newman{1,2,3} \newman{,,,4,5,6}
+\end{example}
+
+Several options allow customization:
+\begin{options}
+ \keyval{angle}{angle}\Module{newman}\Default{0}
+ Default angle.
+ \keyval{scale}{factor}\Module{newman}\Default{1}
+ Scale the whole projection by factor \meta{factor}.
+ \keyval{ring}{tikz}\Module{newman}\Default
+ Customize the ring with \TikZ\ keys.
+ \keyval{atoms}{tikz}\Module{newman}\Default
+ Customize the nodes within which the atoms are set with \TikZ\ keys.
+ \keyval{back-atoms}{tikz}\Module{newman}\Default
+ Explicitly customize the nodes of the back atoms with \TikZ\ keys.
+\end{options}
+
+\begin{example}
+ \chemsetup[newman]{angle=45} \newman{}
+ \newman[scale=.75,ring={draw=blue,fill=blue!20}]{}
+\end{example}
+
+\begin{example}
+ \chemsetup[newman]{atoms={draw=red,fill=red!20,inner sep=2pt,rounded corners}}
+ \newman{1,2,3,4,5,6}
+\end{example}
+
+\begin{example}
+ \chemsetup[newman]{
+ atoms = {draw=red,fill=red!20,inner sep=2pt,rounded corners},
+ back-atoms = {draw=blue,fill=blue!20,inner sep=2pt,rounded corners}
+ }
+ \newman{1,2,3,4,5,6} \newman(170){1,2,3,4,5,6}
+\end{example}
+
+\subsection{The \chemmodule*{orbital} Module}\label{sec:orbital-module}
+The \chemmodule{orbital} module loads the \chemmodule{tikz} module. It
+provides the following command to create orbitals:
+\begin{commands}
+ \command{orbital}[\oarg{options}\marg{type}]
+ Draw an orbital shape of type \meta{type}. This command uses \TikZ\
+ internally.
+\end{commands}
+
+There are the following types available for \meta{type}:
+\begin{center}
+ \code{s} \quad
+ \code{p} \quad
+ \code{sp} \quad
+ \code{sp2} \quad
+ \code{sp3}
+\end{center}
+
+\begin{example}
+ \orbital{s} \orbital{p} \orbital{sp} \orbital{sp2} \orbital{sp3}
+\end{example}
+
+Depending on the type you have different options to modify the orbitals:
+\begin{options}
+ \keychoice{phase}{+,-}\Module{orbital}\Default{+}
+ changes the phase of the orbital (all types)
+ \keyval{scale}{factor}\Module{orbital}\Default{1}
+ changes the size of the orbital (all types)
+ \keyval{color}{color}\Module{orbital}\Default{black}
+ changes the color of the orbital (all types)
+ \keyval{angle}{angle}\Module{orbital}\Default{0}
+ rotates the orbitals with a p contribution counter clockwise (all types
+ except \code{s})
+ \keybool{half}\Module{orbital}\Default{false}
+ displays only half an orbital (only \code{p})
+\end{options}
+
+\begin{example}
+ \orbital{s} \orbital[phase=-]{s}
+ \orbital{p} \orbital[phase=-]{p}
+ \orbital{sp3} \orbital[phase=-]{sp3}
+
+ \orbital[angle=0]{p} \orbital[color=red!50]{p}
+ \orbital[angle=135,scale=1.5]{p} \orbital[half]{p}
+\end{example}
+
+Additionally there are two options, with which the \TikZ\ behaviour can be
+changed.
+\begin{options}
+ \keybool{overlay}\Module{orbital}
+ The orbital \enquote{doesn't need space}; it is displayed with the \TikZ\
+ option \code{overlay}.
+ \keyval{opacity}{num}\Module{orbital}
+ The orbital becomes transparent; \meta{value} can have values between
+ \code{1} (fully opaque) to \code{0} (invisible).
+\end{options}
+\begin{example}
+ \vspace{7mm}
+ \chemsetup[orbital]{
+ overlay,
+ p/color = black!70
+ }
+ \setbondoffset{0pt}
+ \chemfig{
+ ?\orbital{p}
+ -[,1.3]{\orbital[phase=-]{p}}
+ -[:30,1.1]\orbital{p}
+ -[:150,.9]{\orbital[phase=-]{p}}
+ -[4,1.3]\orbital{p}
+ -[:-150,1.1]{\orbital[phase=-]{p}}?
+ }
+ \vspace{7mm}
+\end{example}
+
+\begin{example}
+ \vspace{7mm}
+ \setbondoffset{0pt}
+ \chemsetup[orbital]{
+ overlay ,
+ opacity = .75 ,
+ p/scale = 1.6 ,
+ s/color = blue!50 ,
+ s/scale = 1.6
+ }
+ \chemfig{
+ \orbital{s}
+ -[:-20]{\orbital[scale=2]{p}}
+ {\orbital[half,angle=0]{p}}
+ {\orbital[angle=170,half]{p}}
+ {\orbital[angle=-150,half]{p}}
+ (-[:-150]\orbital{s})-\orbital{s}
+ }
+ \vspace{1cm}
+\end{example}
+
+\subsection{The \chemmodule*{polymers} Module}\label{sec:polymers-module}
+The\sinceversion{5.5} \chemmodule{polymers} module loads the
+\chemmodule{nomenclature} and the \chemmodule{tikz} modules.
+
+\subsubsection{Nomenclature}
+
+The \chemmodule{polymers} module defines a number of \ac{iupac} macros for
+usage inside \cs{iupac} which are used in polymer chemistry.
+
+\paragraph{Copolymers}
+\begin{commands}
+ \iupaccs[co]{copolymer}{unspecified copolymer.}
+ \iupaccs[stat]{statistical}{statistical copolymer.}
+ \iupaccs[ran]{random}{random copolymer.}
+ \iupaccs[alt]{alternating}{alternating copolymer.}
+ \iupaccs[per]{periodic}{periodic copolymer.}
+ \iupaccs{block}{block copolymer.}
+ \iupaccs{graft}{graft copolymer.}
+\end{commands}
+
+\paragraph{Non-linear (Co) Polymers and Polymer Assemblies}
+\begin{commands}
+ \iupaccs{blend}{The blend qualifier.}
+ \iupaccs{comb}{The comb qualifier.}
+ \iupaccs[compl]{complex}{The complex qualifier.}
+ \iupaccs[cyclo]{cyclic}{The cyclic qualifier.}
+ \iupaccs{branch}{The branch qualifier.}
+ \iupaccs[net]{network}{The network qualifier.}
+ \iupaccs[ipn]{ipnetwork}{The interpenetrating network qualifier.}
+ \iupaccs[sipn]{sipnetwork}{The semi-interpenetrating network qualifier.}
+ \iupaccs{star}{The star qualifier.}
+\end{commands}
+
+\subsubsection{Polymer Denotations in \pkg*{chemfig}'s Molecules}
+The \pkg{chemfig} manual proposes some code defining the macros
+\cs*{setpolymerdelim} and \cs*{makebraces} which make it possible to add
+delimiters to \pkg{chemfig} molecules. The \chemmodule{polymers} module
+implements the following macro based on the same idea:
+\begin{commands}
+ \command{makepolymerdelims}[\oarg{options}\marg{height}\oarg{depth}\marg{opening
+ node}\marg{closing node}]
+ The value of \meta{depth} is the same as \meta{height} unless it is
+ specified explicitly. \meta{opening node} and \meta{closing node} are the
+ names of \TikZ' nodes where the delimites are placed.
+\end{commands}
+\begin{options}
+ \keychoice{delimiters}{\Marg{\meta{left}\meta{right}}}\Module{polymers}\Default{[]}
+ This option demands two tokens as argument, the first being the opening
+ brace, the second the closing brace. A dot (\code{.}) denotes an empty
+ delimiter.
+ \keyval{subscript}{subscript}\Module{polymers}\Default{\$n\$}
+ Subscript to the right delimiter.
+ \keyval{superscript}{superscript}\Module{polymers}
+ Superscript to the right delimiter.
+\end{options}
+
+\begin{example}
+ \setatomsep{2em}
+ \chemfig{-[@{op,.75}]CH_2-CH(-[6]Cl)-[@{cl,0.25}]}
+ \makepolymerdelims{5pt}[27pt]{op}{cl}
+ \chemfig{-[@{op,.75}]CH_2-CH(-[6]Cl)-[@{cl,0.25}]}
+ \makepolymerdelims[delimiters=()]{5pt}[27pt]{op}{cl}
+\end{example}
+
+\subsection{The \chemmodule*{reactions} Module}\label{sec:reactions-module}
+The \chemmodule{reactions} module loads the \chemmodule{chemformula} module
+and the \pkg{mathtools} package~\cite{pkg:mathtools}.
+
+\subsubsection{Predefined Environments}
+
+You can use these environments for numbered\ldots
+\begin{environments}
+ \environment{reaction}
+ A single reaction where \chemformula\ code is placed directly in the
+ environment body. A wrapper around the \env*{equation} environment. The
+ environment body is parsed with \cs{ch} or \cs{ce} depending on the value
+ of the \option{formula} option, see
+ section~\vref{sec:chemformula-module}.
+ \environment{reactions}
+ Several aligned reactions. A wrapper around \pkg{amsmath}'s \env*{align}
+ environment. The environment body is parsed with \cs{ch} or \cs{ce}
+ depending on the value of the \option{formula} option, see
+ section~\vref{sec:chemformula-module}.
+\end{environments}
+
+\ldots and their starred versions for unnumbered reactions.
+\begin{environments}
+ \environment{reaction*}
+ A wrapper around the \env*{equation*} environment. The environment body
+ is parsed with \cs{ch} or \cs{ce} depending on the value of the
+ \option{formula} option, see section~\vref{sec:chemformula-module}.
+ \environment{reactions*}
+ A wrapper around \pkg{amsmath}'s \env*{align*} environment. The
+ environment body is parsed with \cs{ch} or \cs{ce} depending on the value
+ of the \option{formula} option, see
+ section~\vref{sec:chemformula-module}.
+\end{environments}
+
+With those environments you can create (un)numbered reaction equations similar
+to mathematical equations.
+
+Theses environments use the \env*{equation}/\env*{equation*} environments or
+the \env*{align}/\env*{align*} environments, respectively, to display the
+reactions.
+
+\begin{example}
+ Reaction with counter:
+ \begin{reaction}
+ A -> B
+ \end{reaction}
+\end{example}
+
+\begin{example}
+ Reaction without counter:
+ \begin{reaction*}
+ C -> D
+ \end{reaction*}
+\end{example}
+
+\begin{example}
+ Several aligned reactions with counter:
+ \begin{reactions}
+ A &-> B + C \\
+ D + E &-> F
+ \end{reactions}
+\end{example}
+
+\begin{example}
+ Several aligned reactions without counter:
+ \begin{reactions*}
+ G &-> H + I \\
+ J + K &-> L
+ \end{reactions*}
+\end{example}
+
+If you want to change the layout of the counter tags, you can use
+\begin{commands}
+ \command*{renewtagform}[\marg{tagname}\oarg{format}\marg{left
+ delimiter}\marg{right delimiter}]
+ Provided by the \pkg{mathtools} package.
+\end{commands}
+or use the following options:
+\begin{options}
+ \keyval{tag-open}{left delimiter}\Module{reactions}\Default{\{}
+ \sinceversion{5.6}The left delimiter.
+ \keyval{tag-close}{right delimiter}\Module{reactions}\Default{\}}
+ \sinceversion{5.6}The right delimiter.
+ \keyval{before-tag}{format}\Module{reactions}\Default
+ \sinceversion{5.6}Code inserted before the tags.
+\end{options}
+
+\begin{example}
+ \chemsetup[reactions]{
+ before-tag = R \textbf ,
+ tag-open = [ ,
+ tag-close = ]
+ }
+ \begin{reaction}
+ H2O + CO2 <<=> H2CO3
+ \end{reaction}
+\end{example}
+
+The use of \AmS math's \cs{intertext} is possible:
+\begin{example}
+ \begin{reactions}
+ A + 2 B &-> 3 C + D "\label{rxn:test}"
+ \intertext{Some text in between aligned reactions}
+ 3 E + F &<=> G + 1/2 H
+ \end{reactions}
+ See reaction~\ref{rxn:test}.
+\end{example}
+
+If\sinceversion{5.6} you are using either \pkg{cleveref} or \pkg{fancyref} the
+\env{reaction} counter is supported already. For \pkg{fancyref} use the
+prefix \code{rct}.
+
+\subsubsection{Own Reactions}
+You can create new types of reactions with the command:
+\begin{commands}
+ \command{NewChemReaction}[\marg{name}\oarg{number of arguments}\marg{math name}]
+ \meta{name} will be the name of the new chem environment. \meta{math name} is
+ the underlying math environment. Gives an error if \meta{name} already
+ exists.
+ \command{RenewChemReaction}[\marg{name}\oarg{number of arguments}\marg{math name}]
+ \meta{name} is the name of the renewed chem environment. \meta{math name} is
+ the underlying math environment. Gives an error if \meta{name} does not exist.
+ \command{DeclareChemReaction}[\marg{name}\oarg{number of arguments}\marg{math name}]
+ \meta{name} will be the name of the chem environment. \meta{math name} is
+ the underlying math environment.
+ \command{ProvideChemReaction}[\marg{name}\oarg{number of arguments}\marg{math name}]
+ \meta{name} will be the name of the new chem environment. \meta{math name} is
+ the underlying math environment. The new environment is only defined if
+ it doesn't exist, yet.
+\end{commands}
+
+\begin{sourcecode}
+ \NewChemReaction{reaction} {equation}
+ \NewChemReaction{reaction*} {equation*}
+ \NewChemReaction{reactions} {align}
+ \NewChemReaction{reactions*}{align*}
+\end{sourcecode}
+
+Let's suppose, you'd like to have the alignment behaviour of the \env{alignat}
+environment for \chemformula\ reactions. You could do the following:
+
+\begin{sourcecode}
+ \NewChemReaction{reactionsat}[1]{alignat}
+\end{sourcecode}
+
+With this the \env{reactionsat} environment is defined.
+\begin{example}
+ \NewChemReaction{reactionsat}[1]{alignat}
+ \NewChemReaction{reactionsat*}[1]{alignat*}
+ \begin{reactionsat}{3}
+ A &-> B &&-> C &&-> D \\
+ aaaaa &-> bbbbb &&-> ccccc &&-> ddddd
+ \end{reactionsat}
+ \begin{reactionsat*}{2}
+ A &-> B & C &-> D \\
+ aaaaa &-> bbbbb &\quad{} ccccc &-> ddddd
+ \end{reactionsat*}
+\end{example}
+
+\subsubsection{List of Reactions}
+
+The \chemmodule{reactions} module also provides a command to display a list of
+the reactions created with the \env{reaction} environment.
+\begin{commands}
+ \command{listofreactions}
+ Print a list of reactions.
+\end{commands}
+\begin{example}
+ \listofreactions
+\end{example}
+
+The output of this list can be modified by two options:
+\begin{options}
+ \keyval{list-name}{name of the
+ list}\Module{reactions}\Default{\cs*{ChemTranslate}\Marg{{list-of-reactions}}}
+ Let's you set the name of the list manually. The default name is language
+ dependent, see section~\vref{sec:lang-module}.
+ \keyval{list-entry}{prefix to each
+ entry}\Module{reactions}\Default{\cs*{ChemTranslate}\Marg{reaction}}
+ Let's you set a prefix to each list entry. The default name is language
+ dependent, see section~\vref{sec:lang-module}.
+ \keyval{list-heading-cmd}{code}\Module{reactions}\Default{\cs*{section}\sarg\Marg{\#1}}
+ The\sinceversion{5.2} macro that is called at the beginning of the list.
+ Inside of \meta{code} \code{\#1} refers to the actual heading of the list.
+ The default setting is not entirely true: if a macro \cs*{chapter} is
+ defined \code{\cs*{chapter}\sarg\Marg{\#1}} is used.
+ \keybool{tocbasic}\Module{reactions}\Default{false}
+ \sinceversion{5.6}If you use a \KOMAScript\ class \emph{or} if you load
+ the \pkg{tocbasic} package \emph{or} if you set this option to \code{true}
+ the list of reactions will be set up using the \pkg{tocbasic} package.
+ This \emph{disables} the \option{list-heading-cmd} option. For a
+ \KOMAScript\ class this means that the list of reactions obeys
+ \KOMAScript's \option*{listof} option.
+\end{options}
+Instead of using the option \option{list-name} you also could redefine
+\cs{reactionlistname}.
+
+The list lists all reactions with a number and disregards reactions without
+number. All reaction environments without star have an optional argument
+which let's you add a description (or caption) for the entry in the list.
+\begin{example}
+ \begin{reaction}[Autoprotolyse]
+ 2 H2O <<=> H3O+ + OH-
+ \end{reaction}
+\end{example}
+
+If you use the \env{reactions} environment this will not work, though. In
+this case you can use
+\begin{commands}
+ \command{AddRxnDesc}[\marg{description}]
+ Add a description to a reaction.
+\end{commands}
+
+\begin{example}
+ \begin{reactions}
+ "\chlewis{0.}{Cl}" + CH4 &
+ -> HCl + "\chlewis{180.}{C}" H3 \AddRxnDesc{first~step~of~chain} \\
+ "\chlewis{180.}{C}" H3 + Cl2 &
+ -> CH3Cl + "\chlewis{0.}{Cl}" \AddRxnDesc{second~step~of~chain}
+ \end{reactions}
+\end{example}
+
+\subsection{The \chemmodule*{redox} Module}\label{sec:redox-module}
+
+The \chemmodule{redox} module loads the modules \chemmodule{tikz} and
+\chemmodule{xfrac}. It also loads the packages
+\pkg{mathtools}~\cite{pkg:mathtools} and \pkg{relsize}~\cite{pkg:relsize}.
+
+\subsubsection{Oxidation Numbers}\label{sec:oxidation-numbers}
+
+Regarding the typesetting of oxidation numbers
+\citetitle{iupac:greenbook}~\cite{iupac:greenbook} says the following:
+\begin{cnltxquote}[{\cite[][p.\,50]{iupac:greenbook}}]
+ Oxidation numbers are denoted by positive or negative Roman numerals or by
+ zero \textelp{}
+
+ \textit{Examples}\quad \ox{7,Mn}, \ox[pos=side]{7,manganese}, \ox{-2,O},
+ \ox{0,Ni}
+\end{cnltxquote}
+
+The following command is provided to set oxidation numbers:
+\begin{commands}
+ \command{ox}[\sarg\oarg{options}\Marg{\meta{number},\meta{atom}}]
+ Places \meta{number} as right superscript to \meta{atom}; \meta{number}
+ has to be a (rational) number! \meta{atom} is treated as a \chemformula\
+ formula, like it would be in \cs{chcpd} (this depends on the setting of
+ the \option{formula} option, see~\vref{sec:chemformula-module}).
+\end{commands}
+
+\begin{example}
+ \ox{+1,Na}, \ox{2,Ca}, \ox{-2,S}, \ox{-1,F}
+\end{example}
+
+There are a number of options that can be used to modify the typeset result:
+\begin{options}
+ \keybool{parse}\Module{redox}\Default{true}
+ When \code{false} an arbitrary entry can be used for \code{<number>}.
+ \keybool{roman}\Module{redox}\Default{false}
+ Switches from roman to arabic numbers.
+ \keychoice{pos}{top,super,side}\Module{redox}\Default{super}
+ \code{top} places \meta{number} above \meta{atom}, \code{super} to the
+ upper right as superscript and \code{side} to the right and inside
+ brackets. Both \code{super} and \code{side} follow \ac{iupac}
+ recommendation, \code{top} does not!
+ \keybool{explicit-sign}\Module{redox}\Default{false}
+ Shows the $+$ for positiv numbers and the $\pm$ for $0$.
+ \keybool{explizit-zero-sign}\Module{redox}\Default{true}
+ Only\sinceversion{5.4} if both \option{explicit-sign} and
+ \option{explicit-zero-sign} are set to \code{true} $\pm0$ will be
+ printed.
+ \keychoice{decimal-marker}{comma,point}\Module{redox}\Default{point}
+ Choice for the decimal marker for formal oxidation numbers like \ox{1.2,X}.
+ \keychoice{align}{center,right}\Module{redox}\Default{center}
+ Center the oxidation number relative to the atom or right-align it.
+ \keyval{side-connect}{code}\Module{redox}\Default{\cs*{,}}
+ Code that is inserted between atom and oxidation number if
+ \keyis{pos}{side} is used.
+ \keyval{text-frac}{cs}\Module{redox}\Default{\cs{chemfrac}\Oarg{text}\Marg{\#1}\Marg{\#2}}
+ The fraction macro that is used for fractions if \keyis{pos}{side} is
+ used. \meta{cs} must be a macro that takes two mandatory arguments, the
+ first for the numerator and the second for the denominator.
+ \keyval{super-frac}{cs}\Module{redox}\Default{\cs{chemfrac}\Oarg{superscript}%
+ \Marg{\#1}\Marg{\#2}}
+ The fraction macro that is used for fractions if \keyis{pos}{top} or
+ \keyis{pos}{super} is used. \meta{cs} must be a macro that takes two
+ mandatory arguments, the first for the numerator and the second for the
+ denominator.
+\end{options}
+
+\begin{example}[side-by-side]
+ \ox[roman=false]{2,Ca} \ox{2,Ca} \\
+ \ox[pos=top]{3,Fe}-Oxide \\
+ \ox[pos=side]{3,Fe}-Oxide \\
+ \ox[parse=false]{?,Mn} \\
+ \ox[pos=top,align=right]{2,Ca}
+\end{example}
+
+The \keyis{pos}{top} variant also can be set with the shortcut \cs{ox}\sarg:
+\begin{example}[side-by-side]
+ \ox{3,Fe} \ox*{3,Fe}
+\end{example}
+
+Using the \option{explicit-sign} option will always show the sign of the
+oxidation number:
+\begin{example}
+ \chemsetup[redox]{explicit-sign = true}
+ \ox{+1,Na}, \ox{2,Ca}, \ox{-2,S}, \ch{"\ox{0,F}" {}2}
+\end{example}
+
+\begin{example}
+ \chemsetup[redox]{pos=top}
+ Compare \ox{-1,O2^2-} to \ch{"\ox{-1,O}" {}2^2-}
+\end{example}
+
+Sometimes one might want to use formal oxidation numbers like \num{.5} or
+\chemfrac{1}{3}:
+\begin{example}[side-by-side]
+ \chemsetup[redox]{pos=top}
+ \ox{.5,Br2}
+ \ch{"\ox{1/3,I}" {}3+}
+
+ \chemsetup[redox]{pos=side}
+ \ox{1/3,I3+}
+\end{example}
+
+The fraction is displayed with the help of the \pkg{xfrac}
+package~\cite{bnd:l3packages}. For more details on how \chemmacros\ uses it
+read section~\vref{sec:xfrac-module}.
+
+\subsubsection{Redox Reactions}\label{sec:redox-reactions}
+
+\chemmacros\ provides two commands to visualize the transfer of electrons in
+redox reactions. Both commands are using \TikZ.
+\begin{commands}
+ \command{OX}[\Marg{\meta{name},\meta{atom}}]
+ Label \meta{atom} with the label \meta{name}.
+ \command{redox}[\Darg{\meta{name1},\meta{name2}}\oarg{tikz}\oarg{num}\marg{text}]
+ Connect two \meta{atom}s previously labelled with \cs{OX}. Only the first
+ argument \Darg{\meta{name1},\meta{name2}} is required, the others are all
+ optional.
+\end{commands}
+
+\cs{OX} places \meta{atom} into a node, which is named with \meta{name}. If
+you have set two \cs{OX}, they can be connected with a line using \cs{redox}.
+To do so the names of the two nodes that are to be connected are written in
+the round braces. Since \cs{redox} draws a \code{tikzpicture} with options
+\code{remember picture,overlay}, the document needs to be \emph{compiled at
+ least two times}.
+
+\begin{example}
+ \vspace{7mm}
+ \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b){oxidation}
+\end{example}
+
+This line can be customized using \TikZ\ keys in \oarg{tikz}:
+\begin{example}
+ \vspace{7mm}
+ \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
+\end{example}
+
+With the argument \oarg{num} the length of the vertical parts of the line can
+be adjusted. The default length is \code{.6em}. This length is multiplied
+with \meta{num}. If you use a negative value the line is placed \emph{below}
+the text.
+\begin{example}
+ \vspace{7mm}
+ \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch
+ \redox(a,b)[->,red]{ox}
+ \redox(a,b)[<-,blue][-1]{red}
+ \vspace{7mm}
+\end{example}
+
+The default length of the vertical lines can be customized with the option
+\begin{options}
+ \keyval{dist}{dim}\Module{redox}\Default{.6em}
+ A \TeX\ dimension.
+\end{options}
+
+\begin{example}
+ \vspace{7mm}
+ \chemsetup{redox/dist=1em}
+ \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
+\end{example}
+
+\begin{options}
+ \keyval{sep}{dim}\Module{redox}\Default{.2em}
+ The option can be used to change the distance between the atom and the
+ beginning of the line.
+\end{options}
+
+\begin{example}
+ \vspace{7mm}
+ \chemsetup{redox/sep=.5em}
+ \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
+\end{example}
+
+\paragraph{Examples}
+\begin{example}
+ \vspace{7mm}
+ \ch{
+ 2 "\OX{o1,Na}" + "\OX{r1,Cl}" {}2
+ ->
+ 2 "\OX{o2,Na}" {}+ + 2 "\OX{r2,Cl}" {}-
+ }
+ \redox(o1,o2){\small OX: $- 2\el$}
+ \redox(r1,r2)[][-1]{\small RED: $+ 2\el$}
+ \vspace{7mm}
+\end{example}
+
+\begin{example}
+ \vspace{7mm}
+ \ch{
+ 2 "\OX{o1,\ox*{0,Na}}" + "\OX{r1,\ox*{0,Cl}}" {}2
+ ->
+ 2 "\OX{o2,\ox*{+1,Na}}" {}+ + 2 "\OX{r2,\ox*{-1,Cl}}" {}-
+ }
+ \redox(o1,o2){\small OX: $- 2\el$}
+ \redox(r1,r2)[][-1]{\small RED: $+ 2\el$}
+ \vspace{7mm}
+\end{example}
+
+\begin{example}
+ \vspace{14mm}
+ \ch{
+ 2 "\OX{o1,\ox*{0,Na}}" + "\OX{r1,\ox*{0,Cl}}" {}2
+ ->
+ 2 "\OX{o2,\ox*{+1,Na}}" {}+ + 2 "\OX{r2,\ox*{-1,Cl}}" {}-
+ }
+ \redox(o1,o2)[draw=red,->][3.33]{\small OX: $- 2\el$}
+ \redox(r1,r2)[draw=blue,->]{\small RED: $+ 2\el$}
+\end{example}
+
+\begin{example}
+ \vspace{7mm}
+ \ch{
+ 2 "\OX{o1,\ox*{0,Na}}" + "\OX{r1,\ox*{0,Cl}}" {}2
+ -> 2 "\OX{o2,\ox*{+1,Na}}" {}+ + 2 "\OX{r2,\ox*{-1,Cl}}" {}-
+ }
+ \redox(o1,o2)[green,-stealth]{\small OX}
+ \redox(r1,r2)[purple,-stealth][-1]{\small RED}
+ \vspace{7mm}
+\end{example}
+
+\subsection{The \chemmodule*{scheme} Module}\label{sec:scheme-module}
+
+The \chemmodule{scheme} module loads the \pkg{chemnum}
+package~\cite{pkg:chemnum} and defines a floating environment
+\showenv{scheme}. That is, it \emph{only} defines this float if no
+environment \env{scheme} exists at the end of the preamble. The module checks
+for different available float defining methods, in \emph{this} order:
+\begin{itemize}
+ \item If the current class is a \KOMAScript\ class \cs*{DeclareNewTOC} will
+ be used.
+ \item If the current class is \cls{memoir}, \cls{memoir}'s methods are used.
+ \item If the package \pkg{tocbasic} has been loaded \cs*{DeclareNewTOC} will
+ be used.
+ \item If the package \pkg{newfloat} has been loaded
+ \cs*{DeclareFloatingEnvironment} will be used.
+ \item \sinceversion{5.1}If the package \pkg{floatrow} has been loaded its
+ method will be used.
+ \item If the package \pkg{float} has been loaded its method will be used.
+ \item If neither of the above the \enquote{manual} method is used. This
+ means the environment is defined the same way like \env*{figure} is
+ defined in the \cls*{article} class or the \cls*{book} class, depending if
+ \cs*{chapter} is defined or not.
+\end{itemize}
+
+The list name and the caption name both are translated to the language
+specified according to the \option{lang} option and the provided translations,
+see section~\vref{sec:lang-module} for details. If you want to manually change
+them then redefine these macros after begin document:
+\begin{commands}
+ \command{listschemename}
+ The name of the list of schemes.
+ \command{schemename}
+ The name used in captions.
+\end{commands}
+The list of schemes is printed as expected with
+\begin{commands}
+ \command{listofschemes}
+\end{commands}
+
+If\sinceversion{5.6} you are using either \pkg{cleveref} or \pkg{fancyref} the
+\env{scheme} environment (or rather its captions) are supported already. For
+\pkg{fancyref} use the prefix \code{sch}.
+
+\subsection{The \chemmodule*{spectroscopy} Module}\label{sec:spectroscopy-module}
+
+The \chemmodule{spectroscopy} module loads the \chemmodule{chemformula} module
+and the \pkg{siunitx} package~\cite{pkg:siunitx}.
+
+\subsubsection{The \cs*{NMR} Command}
+
+When you're trying to find out if a compound is the one you think it is often
+NMR spectroscopy is used. The experimental data are typeset similar to this:
+\begin{center}
+ \NMR(400)[CDCl3] = \num{1.59}
+\end{center}
+The \chemmodule{spectroscopy} module provides a command which simplifies the
+input.
+
+\begin{commands}
+ \command{NMR}[\sarg\Marg{\meta{num},\meta{element}}%
+ \Darg{\meta{num},\meta{unit}}\oarg{solvent}]
+ Typeset nuclear magnetic resonance data. \meta{num} is a valid
+ \pkg{siunitx} number input, \meta{unit} is a valid \pkg{siunitx} unit
+ input. \meta{solvent} is any valid \chemformula\ input as in \cs{chcpd}
+ (this depends on the setting of the \option{formula} option,
+ see~\vref{sec:chemformula-module}).
+\end{commands}
+
+\emph{All} Argument are optional! Without arguments we get:
+\begin{example}[side-by-side]
+ \NMR \par
+ \NMR*
+\end{example}
+
+The first argument specifies the kind of NMR:
+\begin{example}[side-by-side]
+ \NMR{13,C}
+\end{example}
+
+The second argument sets the frequency (in \si{\mega\hertz}):
+\begin{example}[side-by-side]
+ \NMR(400)
+\end{example}
+You can choose another unit:
+\begin{example}[side-by-side]
+ \NMR(4e8,\hertz)
+\end{example}
+Please note that the setup of \pkg{siunitx} also affects this command:
+\begin{example}[side-by-side]
+ \sisetup{exponent-product=\cdot}
+ \NMR(4e8,\hertz)
+\end{example}
+
+The third argument specifies the solvent:
+\begin{example}[side-by-side]
+ \NMR[CDCl3]
+\end{example}
+
+\subsubsection{Short Cuts}
+
+It is possible to define short cut commands for specific nuclei.
+\begin{commands}
+ \command{NewChemNMR}[\marg{cs}\Marg{\meta{num},\meta{atom}}]
+ Define a new shortcut macro for typesetting a certain type of magnetic
+ resonence data. Gives an error if \meta{cs} already exists.
+ \command{DeclareChemNMR}[\marg{cs}\Marg{\meta{num},\meta{atom}}]
+ Define a new shortcut macro for typesetting a certain type of magnetic
+ resonence data. Overwrites an existing macro.
+ \command{RenewChemNMR}[\marg{cs}\Marg{\meta{num},\meta{atom}}]
+ Redefine an existing shortcut macro for typesetting a certain type of
+ magnetic resonence data. Gives an error if \meta{cs} doesn't exist.
+ \command{ProvideChemNMR}[\marg{cs}\Marg{\meta{num},\meta{atom}}]
+ Define a new shortcut macro for typesetting a certain type of magnetic
+ resonence data. \meta{cs} is only defined if it doesn't exist, yet.
+\end{commands}
+
+This defines a command with the same arguments as \cs{NMR} \emph{except} for
+\Marg{\meta{num},\meta{atom}}:
+\begin{example}[side-by-side]
+ \NewChemNMR\HNMR{1,H}%
+ \NewChemNMR\CNMR{13,C}%
+ \CNMR*(100) \par
+ \HNMR*(400)
+\end{example}
+
+\subsubsection{An Environment to Typeset Experimental Data}
+
+The \chemmodule{spectroscopy} module provides an environment to ease the input
+of experimental data.
+\begin{environments}
+ \environment{experimental}
+ Environment for the output of experimental data. Inside the environment
+ the following commands are defined.
+\end{environments}
+\begin{commands}
+ \command{data}[\marg{type}\oarg{specification}]
+ Type of data, \eg\ IR, MS\ldots\ The optional argument takes further
+ specifications which are output in parentheses.
+ \command{data}[\sarg\marg{type}\oarg{specification}]
+ Like \cs{data} but changes the \code{=} into a \code{:}, given that
+ \keyis{use-equal}{true} is used.
+ \command{NMR}[\Marg{\meta{num},\meta{elem}\oarg{coupling
+ core}}\Darg{\meta{num},\meta{unit}}\oarg{solvent}]
+ This command gets an additional argument:
+ \cs{NMR}\Marg{13,C[\textasciicircum 1H]} \NMR{13,C[^1H]}
+ \command{J}[\Darg{\meta{bonds};\meta{nuclei}}\oarg{unit}\marg{list of nums}]
+ Coupling constant, values are input separated by \code{;} (NMR). The
+ arguments \Darg{\meta{bonds};\meta{nuclei}} and \oarg{unit} are optional
+ and enable further specifications of the coupling.
+ \command{\#}[\marg{num}]
+ Number of nuclei (NMR).
+ \command{pos}[\marg{num}]
+ Position of nuclues (NMR).
+ \command{val}[\marg{num}]
+ A number, an alias of \pkg{siunitx}' \cs*{num}\marg{num}.
+ \command{val}[\Marg{\meta{num1}--\meta{num2}}]
+ An alias of \pkg{siunitx}' \cs*{numrange}\marg{num1}\marg{num2}.
+\end{commands}
+
+\begin{example}
+ \begin{experimental}
+ \data{type1} Data.
+ \data{type2}[specifications] More data.
+ \data*{type3} Even more data.
+ \end{experimental}
+\end{example}
+
+\paragraph{Customization}\label{sec:experimental-customization}
+
+The output of the environment and of the NMR commands can be customized be a
+number of options. For historical reasons they all belong to the module
+\module{nmr}.
+\begin{options}
+ \keyval{unit}{unit}\Module{spectroscopy}\Default{\cs*{mega}\cs*{hertz}}
+ The used default unit.
+ \keychoice{nucleus}{\Marg{\meta{num},\meta{atom}}}\Module{spectroscopy}\Default{\Marg{1,H}}
+ The used default nucleus.
+ \keyval{connector}{code}\Module{spectroscopy}\Default{-}
+ Places \meta{code} between the nucleus and the method.
+ \keyval{method}{code}\Module{spectroscopy}\Default{NMR}
+ The measuring method.
+ \keyval{format}{commands}\Module{spectroscopy}\Default
+ For example \cs*{bfseries}.
+ \keyval{nmr-base-format}{commands}\Module{spectroscopy}\Default
+ \sinceversion{5.8}Formatting instructions for the NMR base.
+ \keychoice{pos-number}{side,sub,super}\Module{spectroscopy}\Default{side}
+ Position of the number next to the atom.
+ \keyval{coupling-symbol}{code}\Module{spectroscopy}\Default{J}
+ The symbol used for the coupling constant.
+ \keyval{coupling-unit}{unit}\Module{spectroscopy}\Default{\cs*{hertz}}
+ A \pkg{siunitx} unit.
+ \keychoice{coupling-pos}{side,sub}\Module{spectroscopy}\Default{side}
+ Placement of the coupling nuclei next to the symbol $J$ (or rather the
+ symbol specified with option \option{coupling-symbol}).
+ \keyval{coupling-nuclei-pre}{code}\Module{spectroscopy}\Default{(}
+ Code inserted before the coupling nuclei when \keyis{coupling-pos}{side}.
+ \keyval{coupling-nuclei-post}{code}\Module{spectroscopy}\Default{)}
+ Code inserted after the coupling nuclei when \keyis{coupling-pos}{side}.
+ \keyval{coupling-bonds-pre}{code}\Module{spectroscopy}\Default
+ Code inserted before the coupling bonds.
+ \keyval{coupling-bonds-post}{code}\Module{spectroscopy}\Default{\cs*{!}}
+ Code inserted after the coupling bonds.
+ \keyval{coupling-pos-cs}{cs}\Module{spectroscopy}\Default{\cs*{@firstofone}}
+ Set the macro that prints the number set with the \cs{pos} macro. This
+ needs to be a command with one mandatory argument.
+ \keyval{atom-number-cs}{cs}\Module{spectroscopy}\Default{\cs*{@firstofone}}
+ Set the macro that prints the number set with the \cs{\#} macro. This
+ needs to be a command with one mandatory argument.
+ \keyval{atom-number-space}{dim}\Module{spectroscopy}\Default{.16667em}
+ Horizontal\sinceversion{5.3} space inserted between number and atom
+ (printed by \cs{\#}).
+ \keybool{parse}\Module{spectroscopy}\Default{true}
+ Treat the solvent as \chemformula\ formula (this depends on the setting of
+ the \option{formula} option, see~\vref{sec:chemformula-module}) or not.
+ \keyval{delta}{tokens}\Module{spectroscopy}\Default
+ The \meta{tokens} are added after $\delta$.
+ \keybool{list}\Module{spectroscopy}\Default{false}
+ The environment \env{nmr}[<optionen>]{} is formatted as a list
+ \keyval{list-setup}{setup}\Module{spectroscopy}
+ Setup of the list. See below for the default settings.
+ \keybool{use-equal}\Module{spectroscopy}\Default{false}
+ Add egual sign after \cs{NMR} and \cs{data}.
+\end{options}
+
+The default setup of the list:
+\begin{sourcecode}
+ \topsep\z@skip \partopsep\z@skip
+ \itemsep\z@ \parsep\z@ \itemindent\z@
+ \leftmargin\z@
+\end{sourcecode}
+
+\begin{example}
+ \begin{experimental}[format=\bfseries]
+ \data{type1} Data.
+ \data{type2}[specifications] More data.
+ \data*{type3} Even more data.
+ \end{experimental}
+\end{example}
+
+The command \cs{NMR} and all commands defined through \cs{NewChemNMR}
+can be used like \cs{data} for the NMR data.
+
+\begin{example}
+ \begin{experimental}[format=\bfseries,use-equal]
+ \data{type1} Data.
+ \data{type2}[specifications] More data.
+ \NMR Even more data.
+ \end{experimental}
+\end{example}
+
+\paragraph{An Example}
+The code below is shown with different specifications for \meta{options}.
+Of course options can also be chosen with \cs{chemsetup}.
+
+\begin{sourcecode}
+ \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
+ \begin{experimental}[<optionen>]
+ \data*{yield} \SI{17}{\milli\gram} yellow needles (\SI{0.04}{\milli\mole},
+ \SI{13}{\percent}).
+ %
+ \data{mp.} \SI{277}{\celsius} (DSC).
+ %
+ \NMR(600)[CDCl3] \val{2.01} (s, \#{24}, \pos{5}), \val{2.31} (s, \#{12},
+ \pos{1}), \val{6.72--6.74} (m, \#{2}, \pos{11}), \val{6.82} (s, \#{8},
+ \pos{3}), \val{7.05--7.07} (m, \#{2}, \pos{12}), \val{7.39--7.41} (m, \#{4},
+ \pos{9}), \val{7.48--7.49} (m, \#{4}, \pos{8}).
+ %
+ \NMR{13,C}(150)[CDCl3] \val{21.2} ($+$, \#{4}, \pos{1}), \val{23.4} ($+$,
+ \#{8}, \pos{5}), \val{126.0} ($+$, \#{4}, \pos{9}), \val{128.2} ($+$, \#{8},
+ \pos{3}), \val{130.8} ($+$, \#{2}, \pos{12}), \val{133.6} ($+$, \#{2},
+ \pos{11}), \val{137.0} ($+$, \#{4}, \pos{8}), \val{138.6} (q, \#{4},
+ \pos{2}), \val{140.6} (q, \#{2}, \pos{10}), \val{140.8} (q, \#{8}, \pos{4}),
+ \val{141.8} (q, \#{4}, \pos{6}), \val{145.6} (q, \#{2}, \pos{7}).
+ %
+ \data{MS}[DCP, EI, \SI{60}{\electronvolt}] \val{703} (2, \ch{M+}), \val{582}
+ (1), \val{462} (1), \val{249} (13), \val{120} (41), \val{105} (100).
+ %
+ \data{MS}[\ch{MeOH + H2O + KI}, ESI, \SI{10}{\electronvolt}] \val{720} (100,
+ \ch{M+ + OH-}), \val{368} (\ch{M+ + 2 OH-}).
+ %
+ \data{IR}[KBr] \val{3443} (w), \val{3061} (w), \val{2957} (m), \val{2918}
+ (m), \val{2856} (w), \val{2729} (w), \val{1725} (w), \val{1606} (s),
+ \val{1592} (s), \val{1545} (w), \val{1446} (m), \val{1421} (m), \val{1402}
+ (m), \val{1357} (w), \val{1278} (w), \val{1238} (s), \val{1214} (s),
+ \val{1172} (s), \val{1154} (m), \val{1101} (w), \val{1030} (w), \val{979}
+ (m), \val{874} (m), \val{846} (s), \val{818} (w), \val{798} (m), \val{744}
+ (w), \val{724} (m), \val{663} (w), \val{586} (w), \val{562} (w), \val{515}
+ (w).
+ %
+ \data*{UV-Vis} \SI{386}{\nano\metre} ($\varepsilon = \val{65984}$),
+ \SI{406}{\nano\metre} ($\varepsilon = \val{65378}$).
+ %
+ \data*{quantum yield} $\Phi = \val{0.74+-0.1}$\,.
+ \end{experimental}
+\end{sourcecode}
+
+\paragraph{Nearly Standard}
+Output with these options:
+
+\begin{sourcecode}
+ delta=(ppm),pos-number=sub,use-equal
+\end{sourcecode}
+
+\begin{experimental}[delta=(ppm),pos-number=sub,use-equal]
+ \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
+ \data*{yield} \SI{17}{\milli\gram} yellow needles (\SI{0.04}{\milli\mole},
+ \SI{13}{\percent}).
+ %
+ \data{mp.} \SI{277}{\celsius} (DSC).
+ %
+ \NMR(600)[CDCl3] \val{2.01} (s, \#{24}, \pos{5}), \val{2.31} (s, \#{12},
+ \pos{1}), \val{6.72--6.74} (m, \#{2}, \pos{11}), \val{6.82} (s, \#{8},
+ \pos{3}), \val{7.05--7.07} (m, \#{2}, \pos{12}), \val{7.39--7.41} (m, \#{4},
+ \pos{9}), \val{7.48--7.49} (m, \#{4}, \pos{8}).
+ %
+ \NMR{13,C}(150)[CDCl3] \val{21.2} ($+$, \#{4}, \pos{1}), \val{23.4} ($+$,
+ \#{8}, \pos{5}), \val{126.0} ($+$, \#{4}, \pos{9}), \val{128.2} ($+$, \#{8},
+ \pos{3}), \val{130.8} ($+$, \#{2}, \pos{12}), \val{133.6} ($+$, \#{2},
+ \pos{11}), \val{137.0} ($+$, \#{4}, \pos{8}), \val{138.6} (q, \#{4},
+ \pos{2}), \val{140.6} (q, \#{2}, \pos{10}), \val{140.8} (q, \#{8}, \pos{4}),
+ \val{141.8} (q, \#{4}, \pos{6}), \val{145.6} (q, \#{2}, \pos{7}).
+ %
+ \data{MS}[DCP, EI, \SI{60}{\electronvolt}] \val{703} (2, \ch{M+}), \val{582}
+ (1), \val{462} (1), \val{249} (13), \val{120} (41), \val{105} (100).
+ %
+ \data{MS}[\ch{MeOH + H2O + KI}, ESI, \SI{10}{\electronvolt}] \val{720} (100,
+ \ch{M+ + OH-}), \val{368} (\ch{M+ + 2 OH-}).
+ %
+ \data{IR}[KBr] \val{3443} (w), \val{3061} (w), \val{2957} (m), \val{2918}
+ (m), \val{2856} (w), \val{2729} (w), \val{1725} (w), \val{1606} (s),
+ \val{1592} (s), \val{1545} (w), \val{1446} (m), \val{1421} (m), \val{1402}
+ (m), \val{1357} (w), \val{1278} (w), \val{1238} (s), \val{1214} (s),
+ \val{1172} (s), \val{1154} (m), \val{1101} (w), \val{1030} (w), \val{979}
+ (m), \val{874} (m), \val{846} (s), \val{818} (w), \val{798} (m), \val{744}
+ (w), \val{724} (m), \val{663} (w), \val{586} (w), \val{562} (w), \val{515}
+ (w).
+ %
+ \data*{UV-Vis} \SI{386}{\nano\metre} ($\varepsilon = \val{65984}$),
+ \SI{406}{\nano\metre} ($\varepsilon = \val{65378}$).
+ %
+ \data*{quantum yield} $\Phi = \val{0.74+-0.1}$\,.
+\end{experimental}
+
+\paragraph{Formatted List}
+Output with these options:
+
+\begin{sourcecode}
+ format=\bfseries,delta=(ppm),list=true,use-equal
+\end{sourcecode}
+
+\begin{experimental}[format=\bfseries,delta=(ppm),list=true,use-equal]
+ \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
+ \data*{yield} \SI{17}{\milli\gram} yellow needles (\SI{0.04}{\milli\mole},
+ \SI{13}{\percent}).
+ %
+ \data{mp.} \SI{277}{\celsius} (DSC).
+ %
+ \NMR(600)[CDCl3] \val{2.01} (s, \#{24}, \pos{5}), \val{2.31} (s, \#{12},
+ \pos{1}), \val{6.72--6.74} (m, \#{2}, \pos{11}), \val{6.82} (s, \#{8},
+ \pos{3}), \val{7.05--7.07} (m, \#{2}, \pos{12}), \val{7.39--7.41} (m, \#{4},
+ \pos{9}), \val{7.48--7.49} (m, \#{4}, \pos{8}).
+ %
+ \NMR{13,C}(150)[CDCl3] \val{21.2} ($+$, \#{4}, \pos{1}), \val{23.4} ($+$,
+ \#{8}, \pos{5}), \val{126.0} ($+$, \#{4}, \pos{9}), \val{128.2} ($+$, \#{8},
+ \pos{3}), \val{130.8} ($+$, \#{2}, \pos{12}), \val{133.6} ($+$, \#{2},
+ \pos{11}), \val{137.0} ($+$, \#{4}, \pos{8}), \val{138.6} (q, \#{4},
+ \pos{2}), \val{140.6} (q, \#{2}, \pos{10}), \val{140.8} (q, \#{8}, \pos{4}),
+ \val{141.8} (q, \#{4}, \pos{6}), \val{145.6} (q, \#{2}, \pos{7}).
+ %
+ \data{MS}[DCP, EI, \SI{60}{\electronvolt}] \val{703} (2, \ch{M+}), \val{582}
+ (1), \val{462} (1), \val{249} (13), \val{120} (41), \val{105} (100).
+ %
+ \data{MS}[\ch{MeOH + H2O + KI}, ESI, \SI{10}{\electronvolt}] \val{720} (100,
+ \ch{M+ + OH-}), \val{368} (\ch{M+ + 2 OH-}).
+ %
+ \data{IR}[KBr] \val{3443} (w), \val{3061} (w), \val{2957} (m), \val{2918}
+ (m), \val{2856} (w), \val{2729} (w), \val{1725} (w), \val{1606} (s),
+ \val{1592} (s), \val{1545} (w), \val{1446} (m), \val{1421} (m), \val{1402}
+ (m), \val{1357} (w), \val{1278} (w), \val{1238} (s), \val{1214} (s),
+ \val{1172} (s), \val{1154} (m), \val{1101} (w), \val{1030} (w), \val{979}
+ (m), \val{874} (m), \val{846} (s), \val{818} (w), \val{798} (m), \val{744}
+ (w), \val{724} (m), \val{663} (w), \val{586} (w), \val{562} (w), \val{515}
+ (w).
+ %
+ \data*{UV-Vis} \SI{386}{\nano\metre} ($\varepsilon = \val{65984}$),
+ \SI{406}{\nano\metre} ($\varepsilon = \val{65378}$).
+ %
+ \data*{quantum yield} $\Phi = \val{0.74+-0.1}$\,.
+\end{experimental}
+
+\paragraph{Crazy}
+Output for these options:
+
+\begin{sourcecode}
+ format=\color{red}\itshape,
+ list=true,
+ delta=\textcolor{green}{\ch{M+ + H2O}},
+ pos-number=side,
+ coupling-unit=\mega\gram\per\square\second,
+ list-setup=,
+ use-equal
+\end{sourcecode}
+
+\begin{experimental}[
+ format=\color{red}\itshape,
+ list=true,
+ delta=\textcolor{green}{\ch{M+ + H2O}},
+ pos-number=side,
+ coupling-unit=\mega\gram\per\square\second,
+ list-setup=,use-equal]
+ \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
+ \data*{yield} \SI{17}{\milli\gram} yellow needles (\SI{0.04}{\milli\mole},
+ \SI{13}{\percent}).
+ %
+ \data{mp.} \SI{277}{\celsius} (DSC).
+ %
+ \NMR(600)[CDCl3] \val{2.01} (s, \#{24}, \pos{5}), \val{2.31} (s, \#{12},
+ \pos{1}), \val{6.72--6.74} (m, \#{2}, \pos{11}), \val{6.82} (s, \#{8},
+ \pos{3}), \val{7.05--7.07} (m, \#{2}, \pos{12}), \val{7.39--7.41} (m, \#{4},
+ \pos{9}), \val{7.48--7.49} (m, \#{4}, \pos{8}).
+ %
+ \NMR{13,C}(150)[CDCl3] \val{21.2} ($+$, \#{4}, \pos{1}), \val{23.4} ($+$,
+ \#{8}, \pos{5}), \val{126.0} ($+$, \#{4}, \pos{9}), \val{128.2} ($+$, \#{8},
+ \pos{3}), \val{130.8} ($+$, \#{2}, \pos{12}), \val{133.6} ($+$, \#{2},
+ \pos{11}), \val{137.0} ($+$, \#{4}, \pos{8}), \val{138.6} (q, \#{4},
+ \pos{2}), \val{140.6} (q, \#{2}, \pos{10}), \val{140.8} (q, \#{8}, \pos{4}),
+ \val{141.8} (q, \#{4}, \pos{6}), \val{145.6} (q, \#{2}, \pos{7}).
+ %
+ \data{MS}[DCP, EI, \SI{60}{\electronvolt}] \val{703} (2, \ch{M+}), \val{582}
+ (1), \val{462} (1), \val{249} (13), \val{120} (41), \val{105} (100).
+ %
+ \data{MS}[\ch{MeOH + H2O + KI}, ESI, \SI{10}{\electronvolt}] \val{720} (100,
+ \ch{M+ + OH-}), \val{368} (\ch{M+ + 2 OH-}).
+ %
+ \data{IR}[KBr] \val{3443} (w), \val{3061} (w), \val{2957} (m), \val{2918}
+ (m), \val{2856} (w), \val{2729} (w), \val{1725} (w), \val{1606} (s),
+ \val{1592} (s), \val{1545} (w), \val{1446} (m), \val{1421} (m), \val{1402}
+ (m), \val{1357} (w), \val{1278} (w), \val{1238} (s), \val{1214} (s),
+ \val{1172} (s), \val{1154} (m), \val{1101} (w), \val{1030} (w), \val{979}
+ (m), \val{874} (m), \val{846} (s), \val{818} (w), \val{798} (m), \val{744}
+ (w), \val{724} (m), \val{663} (w), \val{586} (w), \val{562} (w), \val{515}
+ (w).
+ %
+ \data*{UV-Vis} \SI{386}{\nano\metre} ($\varepsilon = \val{65984}$),
+ \SI{406}{\nano\metre} ($\varepsilon = \val{65378}$).
+ %
+ \data*{quantum yield} $\Phi = \val{0.74+-0.1}$\,.
+\end{experimental}
+
+\subsection{The \chemmodule*{thermodynamics} Module}\label{sec:thermodynamics-module}
+
+The \chemmodule{thermodynamics} module loads the \pkg{siunitx}
+package~\cite{pkg:siunitx}.
+
+\subsubsection{The \cs*{state} Macro}
+
+\begin{commands}
+ \command{state}[\oarg{options}\marg{symbol}]
+ Typeset a state variable.
+\end{commands}
+
+This macro can be used to write the thermodynamic state variables.
+\begin{example}
+ \state{A}, \state[subscript-left=f]{G} ,
+ \state[subscript-right=\ch{Na}]{E},
+ \state[superscript-right=\SI{1000}{\celsius}]{H}
+\end{example}
+
+These options are available:
+\begin{options}
+ \keyval{pre}{text}\Module{thermodynamics}\Default{\cs{changestate}}
+ Code inserted before the variable. Inserted in text mode.
+ \keyval{post}{text}\Module{thermodynamics}\Default
+ Code inserted after the variable. Inserted in text mode.
+ \keyval{superscript-left}{text}\Module{thermodynamics}\Default
+ The left superscript. Inserted in text mode.
+ \keyval{superscript-right}{text}\Module{thermodynamics}\Default{\cs{standardstate}}
+ The right superscript. Inserted in text mode.
+ \keyval{superscript}{text}\Module{thermodynamics}
+ An alias of \option{superscript-right}.
+ \keyval{subscript-left}{text}\Module{thermodynamics}\Default
+ The left subscript. Inserted in text mode.
+ \keyval{subscript-right}{text}\Module{thermodynamics}\Default
+ The right subscript. Inserted in text mode.
+ \keyval{subscript}{text}\Module{thermodynamics}
+ An alias of \option{subscript-left}.
+\end{options}
+
+\subsubsection{Thermodynamic Variables}
+
+The \chemmodule{thermodynamics} module provides a few commands for specific
+thermodynamic variables:
+\begin{commands}
+ \command{enthalpy}[\sarg\oarg{options}\darg{subscript}\marg{value}]
+ Typeset the amount of enthalpy.
+ \command{entropy}[\sarg\oarg{options}\darg{subscript}\marg{value}]
+ Typeset the amount of entropy.
+ \command{gibbs}[\sarg\oarg{options}\darg{subscript}\marg{value}]
+ Typeset the amount of Gibbs enthalpy.
+\end{commands}
+
+Their usage is pretty much self-explaining:
+\begin{example}[side-by-side]
+ \enthalpy{123} \par
+ \entropy{123} \par
+ \gibbs{123}
+\end{example}
+The argument \darg{subscript} adds a subscript for specification, \sarg\ hides
+number and unit:
+\begin{example}[side-by-side]
+ \enthalpy(r){123} \par
+ \enthalpy*{123} \par
+\end{example}
+
+\begin{options}
+ \keyval{pre}{text}\Module{thermodynamics}\Default{\cs{changestate}}
+ Code inserted before the variable. Inserted in text mode.
+ \keyval{post}{text}\Module{thermodynamics}\Default
+ Code inserted after the variable. Inserted in text mode.
+ \keyval{superscript-left}{text}\Module{thermodynamics}\Default
+ The left superscript. Inserted in text mode.
+ \keyval{superscript-right}{text}\Module{thermodynamics}\Default{\cs{standardstate}}
+ The right superscript. Inserted in text mode.
+ \keyval{superscript}{text}\Module{thermodynamics}
+ An alias of \option{superscript-right}.
+ \keyval{subscript-left}{text}\Module{thermodynamics}\Default
+ The left subscript. Inserted in text mode.
+ \keyval{subscript-right}{text}\Module{thermodynamics}\Default
+ The right subscript. Inserted in text mode.
+ \keyval{subscript}{text}\Module{thermodynamics}
+ An alias of \option{subscript-left}.
+ \keychoice{subscript-pos}{left,right}\Module{thermodynamics}\Default{left}
+ Determines wether the subscript given in \darg{subscript} is placed to the
+ left or the right of the variable.
+ \keyval{symbol}{symbol}\Module{thermodynamics}\Default
+ The symbol of the variable. Inserted in math mode.
+ \keyval{unit}{unit}\Module{thermodynamics}\Default
+ A valid \pkg{siunitx} unit.
+\end{options}
+
+The default values depend on the command.
+\begin{example}[side-by-side]
+ \enthalpy[unit=\kilo\joule]{-285} \par
+ \gibbs[pre=]{0} \par
+ \entropy[pre=$\Delta$,superscript=]{56.7}
+\end{example}
+The unit is set corresponding to the rules of \pkg{siunitx} and depends on
+its settings:
+\begin{example}[side-by-side]
+ \enthalpy{-1234.56e3} \par
+ \sisetup{
+ per-mode=symbol,
+ exponent-product=\cdot,
+ output-decimal-marker={,},
+ group-four-digits=true
+ }
+ \enthalpy{-1234.56e3}
+\end{example}
+
+\subsubsection{Create New Variables or Redefine Existing Ones}
+
+\begin{commands}
+ \command{NewChemState}[\marg{cs}\marg{options}]
+ Define new state commands like \cs{enthalpy}. Gives an error is \meta{cs}
+ already exists.
+ \command{RenewChemState}[\marg{cs}\marg{options}]
+ Redefine existing state commands.
+ \command{DeclareChemState}[\marg{cs}\marg{options}]
+ Like \cs{NewChemState} but gives now error if \meta{cs} already exists.
+ \command{ProvideChemState}[\marg{cs}\marg{options}]
+ Define new state commands like \cs{enthalpy}. Defines \meta{cs} only if
+ it is not defined, yet.
+\end{commands}
+The argument \meta{options} is a comma separated list of key/value options:
+\begin{options}
+ \keyval{pre}{text}\Module{thermodynamics}\Default{\cs{changestate}}
+ Code inserted before the variable. Inserted in text mode.
+ \keyval{post}{text}\Module{thermodynamics}\Default
+ Code inserted after the variable. Inserted in text mode.
+ \keyval{superscript-left}{text}\Module{thermodynamics}\Default
+ The left superscript. Inserted in text mode.
+ \keyval{superscript-right}{text}\Module{thermodynamics}\Default{\cs{standardstate}}
+ The right superscript.
+ \keyval{superscript}{text}\Module{thermodynamics}
+ An alias of \option{superscript-right}.
+ \keyval{subscript-left}{text}\Module{thermodynamics}\Default
+ The left subscript. Inserted in text mode.
+ \keyval{subscript-right}{text}\Module{thermodynamics}\Default
+ The right subscript. Inserted in text mode.
+ \keyval{subscript}{text}\Module{thermodynamics}
+ An alias of \option{subscript-left}.
+ \keychoice{subscript-pos}{left,right}\Module{thermodynamics}\Default{left}
+ Determines wether the subscript given in \darg{subscript} is placed to the
+ left or the right of the variable.
+ \keyval{symbol}{symbol}\Module{thermodynamics}\Default
+ The symbol of the variable.
+ \keyval{unit}{unit}\Module{thermodynamics}\Default
+ A valid \pkg{siunitx} unit.
+\end{options}
+
+\begin{example}
+ \NewChemState\Helmholtz{ symbol=A , unit=\kilo\joule\per\mole }
+ \NewChemState\ElPot{ symbol=E , subscript-pos=right , superscript= , unit=\volt }
+ \Helmholtz{123.4} \par
+ \ElPot{-1.1} \par
+ \ElPot[superscript=0]($\ch{Sn}|\ch{Sn^2+}||\ch{Pb^2+}|\ch{Pb}$){0.01} \par
+ \RenewChemState\enthalpy{ symbol=h , unit=\joule} \par
+ \enthalpy(f){12.5}
+\end{example}
+
+The existing commands have been defined like this:
+\begin{sourcecode}
+ \NewChemState \enthalpy{ symbol = H, unit = \kilo\joule\per\mole }
+ \NewChemState \entropy { symbol = S, unit = \joule\per\kelvin\per\mole, pre = }
+ \NewChemState \gibbs { symbol = G, unit = \kilo\joule\per\mole }
+\end{sourcecode}
+
+So -- for following thermodynamic conventions -- one could define a molar and
+an absolute variable:
+\begin{example}
+ \RenewChemState\enthalpy{symbol=h,superscript=,unit=\kilo\joule\per\mole}% molar
+ \NewChemState\Enthalpy{symbol=H,superscript=,unit=\kilo\joule}% absolute
+ \enthalpy{-12.3} \Enthalpy{-12.3}
+\end{example}
+
+\subsection{The \chemmodule*{units} Module}\label{sec:units-module}
+
+The \chemmodule{units} module loads the \pkg{siunitx}
+package~\cite{pkg:siunitx}.
+
+In chemistry some non-SI units are very common. \pkg{siunitx} provides the
+command
+\begin{commands}
+ \command*{DeclareSIUnit}[\marg{cs}\marg{unit}]
+ Define \meta{cs} to be a valid unit command inside \pkg{siunitx}' macros
+ \cs*{SI} and \cs*{si} which represents \meta{unit}.
+\end{commands}
+to add arbitrary units. \chemmacros\ uses that command to provide some
+units. Like all \pkg{siunitx} units they're only valid inside
+\cs*{SI}\marg{num}\marg{unit} and \cs*{si}\marg{unit}.
+\begin{commands}
+ \command{atmosphere} \si{\atmosphere}
+ \command{atm} \si{\atm}
+ \command{calory} \si{\calory}
+ \command{cal} \si{\cal}
+ \command{cmc} \si{\cmc} \par
+ The units \cs{cmc}, \cs{molar}, and \cs{Molar} are defined by the
+ package \pkg{chemstyle} as well. \chemmacros\ only defines them, if
+ \pkg{chemstyle} is not loaded.
+ \command{molar} \si{\molar}
+ \command{moLar} \si{\moLar}
+ \command{Molar} \si{\Molar}
+ \command{MolMass} \si{\MolMass}
+ \command{normal} \si{\normal}
+ \command{torr} \si{\torr}
+\end{commands}
+
+By the way: \cs*{mmHg} \si{\mmHg} already is defined by \pkg{siunitx}.
+
+\section{Internal Modules}
+
+\subsection{The \chemmodule*{tikz} Module}\label{sec:tikz-module}
+
+The \chemmodule{tikz} module loads the \pkg{tikz} package~\cite{pkg:pgf} and
+the \TikZ\ library \code{calc}.
+
+\subsubsection{For Users}
+The \chemmodule{tikz} module defines a few arrow tips:
+\begin{tikzcode}
+ \arrowtip{el}
+ An arrow tip: \verbcode+\tikz\draw[-el](0,0)--(1,0);+
+ \tikz\draw[-el](0,0)--(1,0);
+ \arrowtip{left el}
+ An arrow tip: \verbcode+\tikz\draw[-left el](0,0)--(1,0);+
+ \tikz\draw[-left el](0,0)--(1,0);
+ \arrowtip{right el}
+ An arrow tip: \verbcode+\tikz\draw[-right el](0,0)--(1,0);+
+ \tikz\draw[-right el](0,0)--(1,0);
+\end{tikzcode}
+
+The\sinceversion{5.3} \chemmodule{tikz} module also loads the libraries
+\code{calc} and \code{decorations.pathmorphing}. It uses those libraries for
+defining a new decoration \tikzdecoration{wave}.
+\begin{example}[side-by-side]
+ \begin{tikzpicture}
+ \draw[decorate,decoration=wave] (0,0) -- (2,0) ;
+ \end{tikzpicture}
+\end{example}
+
+\subsubsection{For Module Writers}
+The \chemmodule{tikz} module provides some macros for common \TikZ\
+functions. This allows to use expl3's powerful function variants for
+expansion control.
+
+\begin{commands}
+ \explcommand{c_chemmacros_other_colon_tl}
+ A constant tokenlist which contains a colon with category code~12 (other).
+ This is useful since \TikZ\ sometimes expects an other colon and in an
+ expl3 programming environment \code{:} has category code~11 (letter).
+ \explcommand{chemmacros_tikz_picture:nn}[ \marg{options} \marg{code}]
+ Defined as \verbcode+\tikzpicture[{#1}] #2 \endtikzpicture+.
+ \explcommand{chemmacros_tikz:nn}[ \marg{options} \marg{code}]
+ Defined as \verbcode+\tikz[{#1}]{#2}+.
+ \explcommand{chemmacros_tikz_draw:n}[ \marg{options}]
+ Defined as \verbcode+\draw[{#1}]+.
+ \explcommand{chemmacros_tikz_node:n}[ \marg{options}]
+ Defined as \verbcode+\node[{#1}]+.
+ \explcommand{chemmacros_tikz_shade:n}[ \marg{options}]
+ Defined as \verbcode+\shade[{#1}]+.
+ \explcommand{chemmacros_tikz_shadedraw:n}[ \marg{options}]
+ Defined as \verbcode+\shadedraw[{#1}]+.
+ \explcommand{chemmacros_tikz_node_in_draw:n}[ \marg{options}]
+ Defined as \verbcode+node[{#1}]+.
+\end{commands}
+
+\subsection{The \chemmodule*{xfrac} Module}\label{sec:xfrac-module}
+
+The \chemmodule{xfrac} module loads the package
+\pkg{xfrac}~\cite{bnd:l3packages}. For the following explanations it will be
+helpful if you know about said package and how it works first. This module is
+a support module that defines the macro
+\begin{commands}
+ \command{chemfrac}[\oarg{type}\marg{numerator}\marg{denominator}]
+ \meta{type} can either be \code{text} or \code{superscript}.
+\end{commands}
+This macro calls a certain instance of the \pkg{xfrac} \code{text} template,
+depending on the option \meta{type} and the current font family. If used
+\cs{chemfrac} looks if an instance
+\begin{center}
+ \code{chemmacros-frac-\cs*{f@family}-\meta{type}}
+\end{center}
+exists. If yes this instance is used, if no the instance
+\code{chemmacros-frac-default-\meta{type}} is used. The \code{default}
+instances are the same as the ones for \code{cmr}.
+
+\begin{table}
+ \centering
+ \newcommand*\showfrac[1]{%
+ \code{#1} &
+ \fontfamily{#1}\selectfont
+ \chemfrac[text]{2}{3} &
+ \fontfamily{#1}\selectfont
+ \chemfrac[superscript]{2}{3}%
+ }
+ \caption{Predefined \chemmodule{xfrac} \code{text} instances.}
+ \label{tab:xfrac}
+ \begin{tabular}{llcc}
+ \toprule
+ \bfseries font family & \bfseries text & \bfseries superscript \\
+ \midrule
+ \showfrac{cmr} \\
+ \showfrac{lmr} \\
+ \showfrac{LinuxLibertineT-TLF} \\
+ \showfrac{LinuxLibertineT-TOsF} \\
+ \bottomrule
+ \end{tabular}
+\end{table}
+
+The \chemmodule{xfrac} module defines instances some font families, they are
+listed and demonstrated in table~\vref{tab:xfrac}. The \code{superscript}
+type fractions \emph{look} larger than the \code{text} types. The reason is
+that the \code{superscript} types are typically used with a smaller font size.
+Let's take a look at an example where both instances are used:
+\begin{example}[side-by-side]
+ \chemsetup[redox]{pos=top}
+ \code{superscript}:
+ \ch{"\ox{1/3,I}" {}3+}
+
+ \chemsetup[redox]{pos=side}
+ \code{text}: \ox{1/3,I3+}
+
+ \huge
+ \chemsetup[redox]{pos=top}
+ \code{superscript}:
+ \ch{"\ox{1/3,I}" {}3+}
+
+ \chemsetup[redox]{pos=side}
+ \code{text}: \ox{1/3,I3+}
+\end{example}
+
+If you define instances for other families please feel free to submit them to
+me (see section~\vref{sec:submitting-module}) so they can be added to the
+\chemmodule{xfrac} module.
+
+\appendix
+\part{Appendix}
+\section{Own Modules}\label{sec:own-modules}
+\subsection{How To}
+
+If you have additional functionality which you think might be useful as a
+\chemmacros\ module then you can easily write one yourself. The module must
+be a file in a path where \TeX\ can find it following a certain naming
+scheme. The file for a module \chemmodule*{foo} \emph{must be named}
+\code{chemmacros.module.foo.code.tex}.
+
+\begin{commands}
+ \command{ChemModule}[\sarg\marg{name}\marg{description}\oarg{minimal
+ compatibility version}]
+ Register module \meta{name}. The optional argument \meta{minimal
+ compatibility version} ensures that this module is only loaded if the
+ option \option{compatibility} has a high enough version number. If it is
+ omitted the module can be loaded in each version~5.0 or higher.
+\end{commands}
+
+The first line in the file then should look similar to this:
+\begin{sourcecode}
+ \ChemModule{foo}{2015/07/14 description of foo}
+\end{sourcecode}
+This registers module \chemmodule*{foo} which means \chemmacros\ will accept
+this file as a valid module.
+
+Since \chemmacros\ is written using expl3 \cs{ChemModule} starts an expl3
+programming environment. If you don't want that but rather want to write your
+module using traditional \LaTeXe\ methods then use the starred variant:
+\begin{sourcecode}
+ \ChemModule*{foo}{2015/07/14 description of foo}
+\end{sourcecode}
+In both variants \code{@} has category code~11 (letter).
+
+Since new modules very likely might rely on code provided first in a certain
+version of \chemmacros\ you might want to make sure that your module only is
+loaded when the compatibility mode is high enough to provide the features you
+want:
+\begin{sourcecode}
+ \ChemModule{foo}{2015/10/14 description of foo}[5.2]
+\end{sourcecode}
+
+You should be aware that your module \emph{will not be loaded} with
+\verbcode+\usechemmodule{all}+! The pseudo-module \chemmodule{all} contains a
+manually maintained list of the modules that are loaded by it.
+
+If you decide to write your module \chemmodule*{foo} using expl3 and add
+options you want to be able to set using
+\cs{chemsetup}\Oarg{foo}\marg{options} please make sure you define (and set)
+them with the following macros:
+\begin{commands}
+ \explcommand{chemmacros_define_keys:nn}[ \marg{module} \marg{key definitions}]
+ Define l3keys options for the module \meta{module}. This is a wrapper for
+ \explcs*{keys_define:nn} \Marg{chemmacros/\meta{module}} \marg{key
+ definitions}.
+ \explcommand{chemmacros_set_keys:nn}[ \marg{module} \marg{input}]
+ Sets l3keys options for the module \meta{module}. This is a wrapper for
+ \explcs*{keys_set:nn} \Marg{chemmacros/\meta{module}} \marg{input}.
+\end{commands}
+Also (\emph{especially if you consider submitting the module, see
+ section~\vref{sec:submitting-module}}) please follow the expl3 naming
+conventions for variables and functions, \ie, use \code{chemmacros} as expl3
+module name:
+\begin{sourcecode}
+ \tl_new:N \l__chemmacros_my_internal_variable_tl
+ \tl_new:N \l_chemmacros_my_public_variable_tl
+ \cs_new:Npn \__chemmacros_my_internal_function:n #1 { ... }
+ \cs_new_protected:Npn \chemmacros_my_public_function:n #1 { ... }
+ \NewDocumentCommand \publicfunction {m}
+ { \chemmacros_my_public_function:n {#1} }
+\end{sourcecode}
+You will find more details on the naming conventions in \code{interface3.pdf}
+which most likely is available on your system:
+\begin{lbash}
+ texdoc interface3
+\end{lbash}
+If you haven't read section~\vref{sec:base-module} about the \chemmodule{base}
+module, yet, please have a look. There some macros for module writers are
+described. Also other modules define macros for module writers which may be
+useful.
+
+\subsection{Submitting a Module}\label{sec:submitting-module}
+
+If you have written a module and feel it might be useful for other users
+please feel free to contact me and submit the module. I will surely take at
+look at both functionality and code and if I feel that it adds value to
+\chemmacros\ I will add it to the package. Requirement for this is that the
+module is licensed with the \LPPL\ (v1.3 or later) and that I take over
+maintenance (according to the \enquote{maintainer} status of the \lppl).
+
+Please do \emph{not} submit your module via pull request but send me the files
+directly. In the best case you also have a short piece of documentation.
+
+\section{Suggestions, Bug Reports, Support}\label{sec:sugg-bug-reports}
+
+\paragraph{Support}
+If you need support or help with anything regarding \chemmacros\ please use
+the usual support forums
+\begin{itemize}
+ \item \url{http://www.golatex.de/} or
+ \item \url{http://texwelt.de/wissen/} if you speak German,
+ \item \url{http://www.latex-community.org/forum/} or
+ \item \url{http://tex.stackexchange.com/} if you speak English
+\end{itemize}
+or go the \emph{dedicated support forum}
+\begin{itemize}
+ \item \url{http://www.mychemistry.eu/forums/forum/chemmacros/}
+\end{itemize}
+where you can be sure that I will see the question.
+
+\paragraph{Suggestions}
+If you have any suggestions on how \chemmacros\ could be improved, adding
+missing features \etc, please feel free to contact me via
+\email{contact@mychemistry.eu}.
+
+\paragraph{Bug reports}
+If you find any bugs, \ie, errors (something not working as described,
+conflicts with other packages, \ldots) then please go to
+\url{https://github.com/cgnieder/chemmacros/issues/} and open a new issue
+describing the error including a minimal working example.
+
+\end{document}