% arara: xelatex
% arara: biber
% arara: xelatex
% !arara: xelatex
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% ----------------------------------------------------------------------------- 
% - the CHEMMACROS bundle
% - chemmacros_en.tex
% - macros and commands for chemists
% -----------------------------------------------------------------------------
% - Clemens Niederberger
% -
% -----------------------------------------------------------------------------
% - https://bitbucket.org/cgnieder/chemmacros/
% - contact@mychemistry.eu
% -----------------------------------------------------------------------------
% - If you have any ideas, questions, suggestions or bugs to report, please
% - feel free to contact me.
% -----------------------------------------------------------------------------
% - Copyright 2011-2012 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.
% -----------------------------------------------------------------------------
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% if you want to compile this documentation
% a) you'll need the document class `cnpkgdoc' which you can get here:
%    https://bitbucket.org/cgnieder/cnpkgdoc/
%    the class is licensed LPPL 1.3 or later
% b) you need the following compilation order:
%    > xelatex chemmacros_en (2 or probably 3 times)
%    > biber chemmacros_en
%    > xelatex chemmacros_en (2 times)
%
\documentclass[DIV11,toc=index,toc=bib]{cnpkgdoc}
\docsetup{
  pkg      = chemmacros,
  language = en,
  title    = the \Chemmacros\ bundle,
  subtitle = {packages \Chemmacros, \Chemformula\ and \Ghsystem},
  modules  = true,
  code-box = {skipabove=1ex,skipbelow=1ex}
}

% \usepackage{scrhack}
% \usepackage[varioref=false,floats=float]{chemstyle}
\usepackage{chemfig,upgreek,textgreek,booktabs,cancel}
\usepackage[version=3]{mhchem}
\usepackage{hologo}
\newcommand*\pdfTeX{\hologo{pdfTeX}}
\newcommand*\XeTeX{\hologo{XeTeX}}
\newcommand*\LuaTeX{\hologo{LuaTeX}}
\newcommand*\XeLaTeX{\hologo{XeLaTeX}}
\newcommand*\LuaLaTeX{\hologo{LuaLaTeX}}

\usepackage{fnpct}
\usepackage[biblatex]{embrac}
\ChangeEmph{[}[,.02em]{]}[.055em,-.08em]
\ChangeEmph{(}[-.01em,.04em]{)}[.04em,-.05em]

\pagestyle{headings}

\usepackage{acro}
\acsetup{long-format=\scshape}
\DeclareAcronym{ghs}{
  short = GHS ,
  long  = Globally Harmonized System of Classification and Labelling of Chemicals
}
\DeclareAcronym{eu}{
  short = EU ,
  long  = European Union
}
\DeclareAcronym{iupac}{
  short = IUPAC ,
  long  = International Union of Pure and Applied Chemistry
}
\DeclareAcronym{UN}{
  short = UN ,
  long  = United Nations
}
\DeclareAcronym{dvi}{
  short  = dvi ,
  long   = device independent file format ,
  format = \scshape
}
\DeclareAcronym{pdf}{
  short  = pdf ,
  long   = portable document file ,
  format = \scshape
}

\chemsetup[option]{synchronize}
\colorlet{chemformula}{darkgray}

\usepackage{filecontents}

\begin{filecontents*}{\jobname.ist}
 preamble "\\begin{theindex}\n Section titles are indicated \\textbf{bold},
   packages \\textsf{sans serif}, commands \\code{\\textbackslash\\textcolor{code}{brown}},
   options \\textcolor{key}{\\code{green}} and modules (only \\chemmacros)
   \\textcolor{module}{\\code{red}}.\\newline\n\n"
 heading_prefix "{\\bfseries "
 heading_suffix "\\hfil}\\nopagebreak\n"
 headings_flag  1
 delim_0 "\\ \\dotfill\\ "
 delim_1 "\\ \\dotfill\\ "
 delim_2 "\\ \\dotfill\\ "
 delim_r "\\textendash"
 suffix_2p "\\nohyperpage{\\,f.}"
 suffix_3p "\\nohyperpage{\\,ff.}"
\end{filecontents*}

\usepackage[backend=biber,style=alphabetic,maxbibnames=20]{biblatex}
\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 Holmström and Kozo Kuchitsu and Roberto Marquardt and Ian Mills and
    Franco Pavese and Martin Quack and Jürgen Stohner and Herbert L. Strauss and
    Michio Takami and Anders J Thor},
  title     = {“Quantities, Symbols and Units in Physical Chemistry”, \acs{iupac}
    Green Book},
  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},
  year      = {2005},
  publisher = { \acs{iupac} \&\ RSC Publishing, Cambridge},
  isbn      = {0-85404-438-8}
}
@misc{eu:ghsystem_regulation,
  author   = {{The 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}
}
\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
  }

\newcommand*\chemformula{{\scshape\textcolor{cnpkgblue}{chemformula}}\xspace}
\newcommand*\ghsystem{{\scshape\textcolor{cnpkgblue}{ghsystem}}\xspace}

\newcommand*\Chemmacros{{\fontspec[Color=cnpkgblue,Scale=1.2]{Linux Biolinum Shadow O}chemmacros}}
\newcommand*\Chemformula{{\fontspec[Color=cnpkgblue,Scale=1.2]{Linux Biolinum Shadow O}chemformula}}
\newcommand*\Ghsystem{{\fontspec[Color=cnpkgblue,Scale=1.2]{Linux Biolinum Shadow O}ghsystem}}

\renewcommand*\AmS{\hologo{AmS}}
% \newcommand*\pdfTeX{\hologo{pdfTeX}}
% \renewcommand*\LuaTeX{\hologo{LuaTeX}}

\TitlePicture{%
 \ch[font-spec={[Color=chemformula]Augie}]{ 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)[red,-cf]{\small\ch[font-spec={[Color=red]Augie},math-space=.3em]{$-$ 2 e-}}
 \redox(r1,r2)[blue,-cf][-1]{\small\ch[font-spec={[Color=blue]Augie},math-space=.3em]{$+$ 2 e-}}}

\addcmds{
  a,abinitio,AddRxnDesc,anti,aq,aqi,
  b,ba,bond,bottomrule,bridge,
  cancel,cd,cdot,ce,cee,celsius,centering,chemabove,Chemalpha,Chembeta,Chemgamma,
    Chemdelta,ChemDelta,chemfig,chemname,Chemomega,chemsetup,cip,cis,ch,cnsetup,
    CNMR,color,cstsetup,
  d,D,data,DeclareChemArrow,DeclareChemBond,DeclareChemBondAlias,DeclareChemIUPAC,
    DeclareChemLatin,DeclareChemNMR,DeclareChemParticle,DeclareChemPhase,
    DeclareChemReaction,DeclareChemState,DeclareInstance,DeclareSIUnit,definecolor,
    delm,delp,Delta,Dfi,draw,
  E,el,electronvolt,ElPot,endo,Enthalpy,enthalpy,Entropy,
  footnotesize,fmch,fpch,fscrm,fscrp,
  g,gas,ghs,ghslistall,ghspic,Gibbs,glqq,gram,grqq,
  H,hapto,HNMR,Helmholtz,hertz,hspace,
  includegraphics,insitu,intertext,invacuo,iupac,IUPAC,J,joule,
  Ka,Kb,kilo,Kw,
  L,latin,lewis,Lewis,Lfi,listofreactions,lqd,ltn,
  mch,mega,meta,metre,mhName,midrule,milli,mmHg,mole,
  N,nano,nicefrac,newman,NMR,Nu,Nuc,num,numrange,
  O,ominus,orbital,ortho,oplus,ox,OX,
  p,P,para,pch,per,percent,pgfarrowsdeclarealias,pgfarrowsrenewalias,pH,phase,
    photon,pKa,pKb,pOH,pos,positron,Pot,prt,
  R,Rad,redox,RenewChemArrow,RenewChemBond,RenewChemIUPAC,RenewChemLatin,RenewChemNMR,
    RenewChemParticle,RenewChemPhase,RenewChemState,renewtagform,rightarrow,
  S,Sf,sample,scriptscriptstyle,scrm,scrp,second,setatomsep,setbondoffset,sfrac,
    shorthandoff,ShowChemArrow,ShowChemBond,si,SI,sisetup,sld,Sod,square,State,
    subsection,
  textcolor,textendash,textsuperscript,tiny,toprule,trans,
  upbeta,upeta,upgamma,
  val,volt,vphantom,vspave,
  w,xspace,Z}

\usepackage{imakeidx}
\makeindex[columns=3,intoc,options={-sl \jobname.ist}]

\begin{document}
\chemsetup[chemformula]{
  font-spec =
    {[Color=chemformula,Numbers={Proportional,Lining}]Latin Modern Sans}
}
\def\glqq{„}
\def\grqq{“}

\part{Preliminaries}\secidx{PRELIMINARIES}
\section{Licence, Requirements and README}
The \chemmacros bundle underlies the \LaTeX\ project public license (lppl)
version 1.3 or later (\url{http://www.latex-project.org/lppl.txt}) and has the
status ``maintained.''

The \chemmacros bundle needs the bundles \paket{l3kernel} and \paket{l3packages}.
It also needs the packages \paket{siunitx}, \paket{mathtools}, \paket{bm},
\paket{nicefrac} and \paket{environ} as well as \paket*{tikz}\footnote{CTAN:
\href{http://www.ctan.org/pkg/pgf/}{pgf}} and the \TikZ libraries \code{calc}
and \code{arrows}.

Package option \key{bpchem} (section~\ref{sec:optionen}) needs the package
\paket{bpchem}, package option \key{xspace} needs the package \paket{xspace} and
package option \key{method}{mhchem} needs the package \paket{mhchem}.

With v3.0 the \chemmacros package has been bundled with the new packages
\chemformula and \ghsystem. \chemformula provides an alternative to \paket{mhchem}.
This leads to some internal changes in \chemmacros. On the same time the
documentation has been redesigned.

You might remember that \chemmacros' options all belong to different modules, see
section~\ref{sec:setup} for further information. These are typeset in the left
margin when the option is first mentioned. In section~\ref{sec:overview} all options
and the module they belong to are listed. Throughout the document options are
typeset \textcolor{key}{\code{green}} and modules \textcolor{module}{\code{red}}.

The package \ghsystem needs the packages \chemmacros, \paket{tabu}, \paket{longtable},
\paket{ifpdf} and \paket{graphicx}. \ghsystem has no own package options but
passes all options on to \chemmacros.

\achtung{There are some deprecated commands and options which are not explained
in the manual any more but still exist to ensure backwards compatibility. These
commands issue a warning. They may be dropped some time in the future.}

\section{Motivation and Background}
\chemmacros started some years ago as a growing list of custom macros that I
frequently used. I cannot completely recall when and why I decided to release them
as a package. Well \textendash\ here we go and you might find it useful, too, I
hope.

Both the macros and their functionality have changed over time and quite a lot
have been added. Many things have been unified and what's probably most important:
many possibilities to customize have been added, too.

Probably every chemist using \LaTeXe\ is aware of the great \paket{mhchem} package
by Martin Hensel. There have always been some difficulties intertwining it with
\chemmacros, though. Also, some other minor points in \paket{mhchem} always
bothered me, but they hardly seemed enough for a new package. They weren't even
enough for a feature request to the \paket{mhchem} author. The challenge and the
fun of creating a new package and the wish for a highly customizable alternative
led to \chemformula after all.

\chemformula works very similar to \paket{mhchem} but is more strict as to how
compounds, stoichiometric factors and arrows are input. In the same time
\chemformula offers possibilities to customize the output that \paket{mhchem} does
not. Since \chemformula is meant as an \emph{alternative} to \paket{mhchem}
\chemmacros offers a package option allowing you to choose which one of the two
is used. The default however is \chemmacros own way: \chemformula.

As a chemist you are probably aware of the fact that the \acl{UN} have developed
the \ac{ghs} as a global replacement for the various different systems in different
countries. While it has not been implemented by all countries
yet~\cite{unece:ghsystem_implementation}, it is only a matter of time.

The package \ghsystem now enables you to typeset all the hazard and precautionary
statements and pictograms in a very easy way. The statements are taken from \acs{eu}
regulation 1272/2008~\cite{eu:ghsystem_regulation}.

There are four points I hope I have achieved with this bundle:
\begin{itemize}
 \item intuitive usage as far as the syntax of the commands is concerned
 \item the commands shall not only make typesetting easier and faster but also the
   document source more readable with respect to semantics
   (\code{\cmd{ortho}-dichlorobenzene} is easier to read and understand than
   \code{\cmd*{textsl}{o}-dichlorobenzene})
 \item as much customizability as I could think of so every user can adapt the
   commands to his or her own wishes
 \item default settings compliant with the recommendations of the \acf{iupac}.
\end{itemize}
Especially the last point needed some pushing from users to get things right in
many places. If you find anything not compliant with \ac{iupac} recommendations%
\footnote{This does not concern the \cmd{ox} command. The \ac{iupac} version is
\cmd{ox}*.} I would welcome an email very much!

In a package this large with older parts and rather new parts (which have to be
considered being in beta state) it is unavoidable that there are flaws and bugs.
I am very keen on correcting and improving this package, so please: if you find
anything that bothers you and may it be just so small please send me a short email
and I'll see what I can do. I would especially like feedback on \chemformula (see
part~\ref{part:chemformula}) and \ghsystem (see part~\ref{part:ghsystem}) but also
welcome feedback on every other part of this bundle.

\section{Installation, Loading the Bundle}\secidx{Loading the Bundle}\secidx{Installation}
The bundle comes with three style files\footnote{Those ending \code{sty}.}, a
directory called \code{language/} containing the language-definition files for
\ac{ghs} (ending \code{def}), and a directory \code{pictures/} containing \code{eps},
\code{pdf}, \code{jpg} and \code{png} files (the \ac{ghs} pictograms). If you install
the bundle manually \emph{please make sure to place the directories \code{language/}
and \code{pictures/} in the \emph{same} directory as the style files}.

Loading \chemmacros with
\begin{beispiel}[code only]
 \usepackage{chemmacros} % `chemmacros', `chemformula' and `ghsystem' are loaded
\end{beispiel}
will also load \chemformula and \ghsystem. However, you can prevent \chemmacros
from loading \ghsystem:
\begin{beispiel}[code only]
 \usepackage[ghsystem=false]{chemmacros} % `chemmacros' and `chemformula' are loaded
\end{beispiel}

Loading \chemformula or \ghsystem explicitly is possible and will also load
\chemmacros if it hasn't been loaded yet, and will therefore implicitly load the
other package, too.
\begin{beispiel}[code only]
 \usepackage{chemformula}
 or
 \usepackage{ghsystem}
\end{beispiel}

However, it is recommended to simply use \lstinline=\usepackage{chemmacros}= and
setup the required options with \lstinline=\chemsetup= (also see section~\ref{sec:setup}).
\secidx*{Installation}\secidx*{Loading the Bundle}

\section{Package Options}\label{sec:optionen}\secidx{Package Options}
\chemmacros has several package options. They all are used as key/value pairs like
\begin{beispiel}[code only]
 \usepackage[option1 = <value1>, option2 = <value2>]{chemmacros}
\end{beispiel}
Some also can be used without value (\lstinline+\usepackage[option1]{chemmacros}+),
which means that the \default{underlined} value is used.

Both \chemformula and \ghsystem don't have package options of their own. If you
load them explicitly any given option will silently fail. Options can then only
be set using the setup command.
\begin{beschreibung}
 % bpchem
 \option[option]{bpchem}{\default{true}|false} This option loads the package
   \paket{bpchem} and adjusts the layout of the \cmd{NMR} command to the \paket{bpchem}
   commands \lstinline+\HNMR+ and \lstinline+\CNMR+. (default = \code{false})
 % circled
 \option[option]{circled}{\default{formal}|all|none} \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 (default = \code{formal})
 % circletype
 \option[option]{circletype}{\default{chem}|math} This option switches between
   two kinds of circled charge symbols: \cmd{fplus} \fplus\ and \lstinline+$\oplus$+
   $\oplus$. (default = \code{chem})
 % cmversion
 \option[option]{cmversion}{1|2|bundle} This option restores the old definitions
   of some commands, so documents set with v1.* will still compile correctly.
   (default = \code{bundle}). Actually \code{2} and \code{bundle} are only aliases.
   \emph{This option can only be chosen in the preamble}.
 % ghsystem
 \option[option]{ghsystem}{\default{true}|false} Disable the use of the \ghsystem
   package. Setting \key{ghs}{false} will prevent \chemmacros from loading \ghsystem.
   (default = \code{true})
 % greek
 \option[option]{greek}{\default{auto}|math|textgreek|upgreek} This Option determines
   how the letters \cmd{Chemalpha} and friends are typeset. See page~\pageref{desc:upgreek}
   for more information. \emph{This option can only be chosen in the preamble}.
   Please note that this options \emph{does not load either \paket{upgreek} nor
   \paket{textgreek}}! It only determines which one to choose if available. The
   option will detect if either \paket{upgreek} or \paket{textgreek} have been
   loaded and use them if available. If you explicitly choose \code{upgreek} or
   \code{textgreek} you also have to load the corresponding package.
   (default = \code{auto})
 % iupac
 \option[option]{iupac}{auto|restricted|strict} Take care of how \ac{iupac} naming
   commands are defined, see page~\pageref{desc:iupac} (default = \code{auto})
 % language
 \option[option]{language}{american|british|english|french|german|italian|ngerman}
   Load language specific options. \code{english}, \code{american} and \code{british}
   are aliases, as are \code{german} and \code{ngerman}. \emph{This option can only
   be chosen in the preamble}. (default = \code{english}).
 % method
 \option[option]{method}{\default{chemformula}|mhchem} You can choose the method
   which \chemmacros will use for the reaction environments (see section~\ref{sec:reactions})
   and the typesetting of the particles (see section~\ref{sec:teilchen}). (default
   = \code{chemformula}). \emph{This option can only be chosen in the preamble}.
 % Nu
 \option[option]{Nu}{\default{chemmacros}|mathspec} The package \paket{mathspec}
   also defines a macro \cmd{Nu}. This option chooses which definition holds, see
   page~\pageref{Nu}. (default = \code{chemmacros}). \emph{This option can only
   be chosen in the preamble}.
 % strict
 \option[option]{strict}{\default{true}|false} Setting \key{strict}{true} will
   turn all warning messages into erros messages. (default = \code{false})
 % synchronize
 \option[option]{synchronize}{\default{true}|false} The setting \code{true} will
   tell \chemmacros the adapt the font settings of \chemformula if that method has
   been chosen (default = \code{false}). In order to demonstrate this feature this
   document is set with \key{synchronize}{true} and the \chemformula setting
   \lstinline+\chemsetup[chemformula]{font-spec={[Color=darkgray]Latin Modern Sans}}+.
 % xspace
 \option[option]{xspace}{\default{true}|false} With this option most commands are
   defined with a \lstinline+\xspace+. (default = \code{true})
\end{beschreibung}
\secidx*{Package Options}

\section{Setup}\label{sec:setup}\secidx{Setup}
Various of \chemmacros', \chemformula's and \ghsystem's commands have key/value
pairs with which they can be customized. Most times they can be used as (optional)
argument of the commands themselves. They also can most times be used with the
\cmd{chemsetup} command.
\begin{beschreibung}
 \Befehl{chemsetup}[<module>]{<key> = <value>} or
 \Befehl{chemsetup}{<module>/<key> = <value>}
\end{beschreibung}
The keys each belong to a module, which defines for which commands they are
intended for. If a key is presented, you'll see the module to which it belongs
in the left margin. You have two ways to use keys with the \cmd{chemsetup}, as
you can see above.

The package options can also be seen as keys belonging to the module
\textcolor{module}{\code{option}}. This means they can also be used with the
\cmd{chemsetup} command (except for the option \key[option]{version}{1/2/3}).
\begin{beispiel}
 \chemsetup[option]{circled=none}\mch\ \pch\ \fmch\ \fpch\ \el\ \prt \\
 \chemsetup[option]{circled=formal}\mch\ \pch\ \fmch\ \fpch\ \el\ \prt \\
 \chemsetup[option]{circletype=math}\mch\ \pch\ \fmch\ \fpch\ \el\ \prt \\
 \chemsetup{option/circletype=chem,option/circled=all}\mch\ \pch\ \fmch\ \fpch\ \el\ \prt \\
 \chemsetup{option/circletype=math}\mch\ \pch\ \fmch\ \fpch\ \el\ \prt
\end{beispiel}
Keys \emph{not} belonging to a module \emph{cannot} be used with \cmd{chemsetup}!

All options of \chemformula belong to the module \textcolor{module}{\code{chemformula}}
and all of \ghsystem's options belong to the module \textcolor{module}{\code{ghs}}.
\secidx*{Setup}

\section{Language Settings}\label{sec:languages}\secidx{Language Settings}
\subsection{Supported Languages}
By choosing the option
\begin{beispiel}[code only]
 \chemsetup[option]{language=<language>}
\end{beispiel}
you can set one of these languages: \code{american}, \code{british},\ code{english},
\code{french}, \code{german}, \code{italian} and \code{ngerman}. The languages
\code{american}, \code{british} and \code{english} are aliases, as are \code{german}
and \code{ngerman}.

These translate
\begin{itemize}
 \item The header of the list of reactions.
 \item The beginning of the entries in the list of reactions.
 \item The H- and P-statements of the \ac{ghs}.
\end{itemize}

\achtung{Please note, that the \ac{ghs} statements are not provided in all languages,
see also section~\ref{sec:ghsystem_language}.}

\subsection{Specialties}
\subsubsection{German}
If you choose \code{german/ngerman} the phase commands \cmd{sld} and \cmd{lqd}
and the command \cmd{pKa} are translated.

\subsubsection{Italian}
\DeclareChemIUPAC{\ter}{\textit{ter}}\DeclareChemIUPAC{\sin}{\textit{sin}}%
Choosing the language \code{italian} defines two additional \ac{iupac} commands:
\begin{beschreibung}
 \befehl{ter} \iupac{\ter}
 \befehl{sin} \iupac{\sin}
\end{beschreibung}
\secidx*{Language Settings}

\section{News}\secidx{News}
\subsection{Version 3.3}
\begin{itemize}
 \item With v3.3 there is the environment \env{experimental}{}, see
   section~\ref{sec:spektroskopie}. It can be used together with some new options
   and commands for the consistent typesetting of experimental data.
 \item The environment \env{reaction}{} and its kin can now cope with \lstinline+\label+,
 \lstinline+\ref+ and \lstinline+\intertext+, see section~\ref{sec:reactions}.
 \item The package options \key{german} and \key{ngerman} are deprecated, the
   replacement is \key{language}, see page~\pageref{key:option_language} and
   section~\ref{sec:languages} from page~\pageref{sec:languages}.
 \item The package option \key{upgreek} got renamed into \key{greek}.
 \item Some additional \code{\textbackslash\textcolor{code}{Chem<greekletter>}}-commands
   are provided, see section~\ref{sec:teilchen}.
\end{itemize}

\subsection{Version 3.3a}
\begin{itemize}
 \item The \ac{iupac} commands \cmd{hapto} and \cmd{bridge} are new.
 \item The H and P statements now are available in Italian.
\end{itemize}

\subsection{Version 3.3d}
\begin{itemize}
 \item \code{pdf} versions of the \ac{ghs} pictograms.
 \item New default values for bond length and bond offset, see
   page~\pageref{ssec:compounds:customization}.
 \item New option \key{bond-style}, see page~\pageref{ssec:compounds:customization}.
 \item new option \key{cip-kern}, see page~\pageref{par:cip}.
\end{itemize}

\subsection{Version 3.4}
\begin{itemize}
 \item \chemmacros got an Italian manual, many thanks to Jonas Rivetti who
   volunteered to not only translate the H \&\ P statements but also this
   documentation!
 \item the command \cmd{bond} which allows to use other bonds than single, double
   and triple, see section~\ref{ssec:bonds}. I wanted to add this for a long time!
 \item a few changes to the looks of the radical point and new options to customize
   it, see section~\ref{ssec:compounds:customization}.
\end{itemize}

\secidx*{News}\secidx*{PRELIMINARIES}

\part{\texorpdfstring{\Chemmacros}{chemmacros}}\secidx{CHEMMACROS}\label{part:chemmacros}
\section{Particles, Ions and Symbols}\label{sec:teilchen}\secidx{Particles, Ions and Symbols}
\subsection{Predefined}\secidx[predefined]{Particles, Ions and Symbols}
\chemmacros defines some simple macros for displaying often needed particles and
symbols. Please note, that they're displayed differently depending on the package
options used, see section~\ref{sec:optionen}. These commands can be used in text
as well as in math mode.
\begin{beschreibung}
 \befehl{Hpl} \Hpl (proton)
 \befehl{Hyd} \Hyd (hydroxide)
 \befehl{HtO} \HtO (oxonium ion) (\textbf{H} \textbf{t}hree \textbf{O})
 \befehl{water} \water
 \befehl{el} \el (electron)
 \befehl{prt} \prt (proton)
 \befehl{ntr} \ntr (neutron)
 \befehl{Nu} \Nu (nucleophile). The package \paket{mathspec} also defines a macro
   \cmd{Nu}. If you chose package option \key[option]{Nu}{mathspec} \chemmacros
   defines \cmd{Nuc} instead\label{Nu}.
 \befehl{El} \El (electrophile)
 \befehl{ba} \ba (base)
 \befehl{fplus} \fplus
 \befehl{fminus} \fminus
 \befehl{transitionstatesymbol} \transitionstatesymbol
 \befehl{standardstate} \standardstate. This symbol is only provided by \chemmacros,
   if the package \paket{chemstyle} is not loaded; the idea is borrowed from
   there\footnote{many thanks to the package author \href{http://www.texdev.net/}{Joseph Wright}.}.
 \befehl{Chemalpha} \Chemalpha
 \befehl{Chembeta} \Chembeta
 \befehl{Chemgamma} \Chemgamma
 \befehl{Chemdelta} \Chemdelta
 \befehl{Chemepsilon} \Chemepsilon
 \befehl{Chemeta} \Chemeta
 \befehl{Chemkappa} \Chemkappa
 \befehl{Chemmu} \Chemmu
 \befehl{Chemnu} \Chemnu
 \befehl{Chemrho} \Chemrho
 \befehl{Chempi} \Chempi
 \befehl{Chemsigma} \Chemsigma
 \befehl{Chemomega} \Chemomega
 \befehl{ChemDelta} \ChemDelta
\end{beschreibung}

\achtung{The command \cmd{Rad} has been dropped!}

The two particles \cmd{Nu} and \cmd{ba} can be modified. To do that you use the
option
\begin{beschreibung}
 \Option[particle]{elpair}{false|\default{dots}|dash}.
\end{beschreibung}
It only has any effect, if the package \paket{chemfig} is loaded, since it uses
it's command \lstinline+\Lewis+.
\begin{beispiel}
 % needs package `chemfig'
 \ba[elpair] \Nu[elpair=dash]
 
 \chemsetup[particle]{elpair}
 \ba \Nu
\end{beispiel}

\label{desc:upgreek}The greek letters aren't newly defined symbols but are
defined differently depending on the packages you've loaded. The default definition
is the corresponding math letter. If you have loaded the \paket{textgreek} package
the letters are taken from there, and if you have loaded the package \paket{upgreek}
the macros of that package are used. This documentation uses \paket{upgreek} for
instance. If you load both \paket{upgreek} and \paket{textgreek} the letters from
\paket{upgreek} are used.

If you don't want \chemmacros to use a package automatically but want to decide
for yourself, there is the option \key[option]{greek}. Table~\ref{tab:upgreek_mode}
shows the different styles for some of the letters.

\begin{table}[h]
 \centering
 \begin{tabular}{lccc}\toprule
                  & math     & upgreek    & textgreek \\\midrule
  \cmd{Chemalpha} & $\alpha$ & $\upalpha$ & \textalpha \\
  \cmd{Chembeta}  & $\beta$  & $\upbeta$  & \textbeta \\
  \cmd{ChemDelta} & $\Delta$ & $\Updelta$ & \textDelta \\ \bottomrule
 \end{tabular}
 \caption{The greek letters}\label{tab:upgreek_mode}
\end{table}

The reason why \chemmacros defines these macros in the first place is \ac{iupac}
compliance. \ac{iupac} recommends to use upright greek letters in nomenclature.

\begin{zitat}[{\ac{iupac} Green Book {\cite[][p.\,9]{iupac:greenbook}}}]
 Greek letters are used in systematic organic, inorganic, macromolecular and
 biochemical nomenclature. These should be roman (upright), since they are not
 symbols for physical quantities.
\end{zitat}

\chemmacros uses these commands now to defined nomenclature commands, see page~\pageref{par:greek_letters}.

\subsection{Own Particles}\secidx[own]{Particles, Ions and Symbols}
Surely sometimes it can be handy to have other particle macros defined such as
\lstinline+\positron+ or \lstinline+\photon+. This can easily be done with this
command:
\begin{beschreibung}
 \Befehl{DeclareChemParticle}{<cmd>}\ma{<definition>}
 \Befehl{RenewChemParticle}{<cmd>}\ma{<definition>}
\end{beschreibung}
Depending on the \key{method} you chose as option the \code{<definition>} will
either be a formula defined with \paket{mhchem} or with \chemformula. The particle
defined this way behaves like the predefined ones with one exception: if you chose
\key{method}{mhchem} the particle \emph{will not} obey the option \key{circled}.
If you want formal charges with this method you need to use \chemmacros' commands
(see section~\ref{sec:ladungen}) explicitly. If you chose \key{method}{chemformula}
the partictle \emph{will} obey the \key{circled} option.
\begin{beispiel}
 % uses the `upgreek' package
 \DeclareChemParticle{\positron}{$\upbeta$+}
 \DeclareChemParticle{\photon}{$\upgamma$}
 \RenewChemParticle{\el}{$\upbeta$-}
 \positron\ \photon\ \el
\end{beispiel}
\cmd{DeclareChemParticle} only defines a particle if \code{<cmd>} is not already
used by any other command. If it \emph{is} already used \chemmacros will either
give a warning or an error, depending on the option \key{strict}.
\cmd{RenewChemParticle} \emph{only} defines a particle if \code{<cmd>} \emph{is}
already used and issues a warning/error otherwise.
\secidx*{Particles, Ions and Symbols}

\section{Nomenclature, Stereo Descriptors, Latin Phrases}\label{sec:stereo}
\subsection{\acs{iupac} Names}\secidx{IUPAC Names}
Similar to the \paket{bpchem} package \chemmacros provides a command\footnote{The
idea and the implementation is shamelessly borrowed from \paket*{bpchem} by Bjørn
Pedersen.} to typeset \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{beschreibung}
 \Befehl{iupac}{<IUPAC name>} Inside this command use \cmd{|} and \cmd{-} to
   indicate a breaking point or a breaking dash. Use {\catcode`\^=11\relax\cmd{^}}
   as a shortcut for \lstinline=\textsuperscript=.
\end{beschreibung}

\begin{beispiel}
 \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{beispiel}
The \cmd{iupac} command is more of a semantic command. Most times you can achieve
(nearly) the same thing by using \cmd{-} instead of \cmd{|}, \code{-} instead of
\cmd{-} and \lstinline=\textsuperscript= instead of {\catcode`\^=11\relax\cmd{^}}.

There are some subtleties: \cmd{-} inserts a small space before the hyphen a
removes a small space after it. The command \cmd{|} not only prevents ligatures
but also inserts a small space.
\begin{beispiel}
 \huge\iupac{2,4\-Di\|chlor\|pentan} \\
 2,4-Dichlorpentan
\end{beispiel}

The spaces inserted by these commands can be customized.
\begin{beschreibung}
 \option[iupac]{hyphen-pre-space}{<dim>} Default = \code{.01em}
 \option[iupac]{hyphen-post-space}{<dim>} Default = \code{-.03em}
 \option[iupac]{break-space}{<dim>} Default = \code{.01em}
\end{beschreibung}

The command \cmd{iupac} serves another purpose, too, however. Regardless of the
setting of the \key[option]{iupac} option all the commands presented in this
section are always defined \emph{inside} \cmd{iupac}. Quite a number of the naming
commands have very general names: \cmd{meta}, \cmd{D}, \cmd{E}, \cmd{L}, \cmd{R},
\cmd{S}, \cmd{trans} and so forth. This means they either are predefined already
(\cmd{L} \L) or are easily defined by another package or class (the \paket{cool}
package defines both \cmd{D} and \cmd{E}, for example). In order to give you
control which commands are defined in which way, there is the package option
\key[option]{iupac}\label{desc:iupac}. It has three modes:
\begin{itemize}
 \item \key{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}
   \cmd{iupac}.
 \item \key{iupac}{restricted}: all naming commands are \emph{only} defined inside
   \cmd{iupac}. If the commands are defined by another package they of course
   have that meaning outside. They're not defined outside otherwise.
 \item \key{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
   \cmd{iupac} then.
\end{itemize}
Table~\ref{tab:iupac_modes} demonstrates the different modes.

\begin{table}[h]
 \centering
 \begin{tabular}{lccc}\toprule
                    & auto       & restricted & strict \\\midrule
  \lstinline=\L=         & \L         & \L         & \iupac{\L} \\
  \lstinline=\iupac{\L}= & \iupac{\L} & \iupac{\L} & \iupac{\L} \\
  \lstinline=\D=         & \D         & --         & \D \\
  \lstinline=\iupac{\D}= & \iupac{\D} & \iupac{\D} & \iupac{\D} \\\bottomrule
 \end{tabular}
 \caption{Demonstration of \protect\key{iupac}'s modes.}\label{tab:iupac_modes}
\end{table}

\subsubsection{Predefined Commands}\secidx[predefined]{IUPAC Names}\secidx{Stereo Descriptors and Nomenclature}
The macros in this section are intended to make the writing of \ac{iupac} names more
convenient.

\paragraph{Greek Letters}\label{par:greek_letters}\secidx[greek letters]{IUPAC Names}
Greek letters in compound names are typeset upright. For this there are the packages
\paket{upgreek} and \paket{textgreek}. If you have loaded one of them \chemmacros
typesets the following commands upright:
\begin{beschreibung}
 \befehl{a} \iupac{\a}
 \befehl{b} \iupac{\b}
 \befehl{g} \iupac{\g}
 \befehl{d} \iupac{\d}
 \befehl{k} \iupac{\k}
 \befehl{m} \iupac{\m}
 \befehl{n} \iupac{\n}
 \befehl{w} \iupac{\w}
\end{beschreibung}
\begin{beispiel}
 \iupac{5\a\-androstan\-3\b\-ol} \\
 \iupac{\a\-(tri\|chloro\|methyl)\-\w\-chloro\|poly(1,4\-phenylene\|methylene)}
\end{beispiel}

\paragraph{Hetero Atoms and added Hydrogen}\secidx[hetero atoms]{IUPAC Names}
Attachments to hetero atoms and added hydrogen atoms are indicated by italic
letters~\cite{iupac:greenbook}. \chemmacros defines a few shortcuts for the most
common ones.
\begin{beschreibung}
 \befehl{H} \iupac{\H}
 \befehl{O} \iupac{\O}
 \befehl{N} \iupac{\N}
 \befehl{Sf} \iupac{\Sf}
 \befehl{P} \iupac{\P}
\end{beschreibung}
\begin{beispiel}
 \iupac{\N\-methyl\|benz\|amide} \\
 \iupac{3\H\-pyrrole} \\
 \iupac{\O\-ethyl hexanethioate}
\end{beispiel}

\paragraph{Cahn-Ingold-Prelog}\index{Cahn-Ingold-Prelog}\secidx[Cahn-Ingold-Prelog]{IUPAC Names}\label{par:cip}
\begin{beschreibung}
 \befehl{cip}{<conf>} \eg: \cmd{cip}{R,S} \cip{R,S}
 \befehl{R} \iupac{\R}
 \befehl{S} \iupac{\S}
\end{beschreibung}
Since the command \cmd{S} has another meaning already (\S) it is only available
inside \cmd{iupac} in the default setting.

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{beschreibung}
 \option[iupac]{cip-kern}{<dim>} amount of kerning after the closing parenthesis.
 Default = \code{.075em}
\end{beschreibung}

\paragraph{Fischer}\index{Fischer}\secidx[Fischer]{IUPAC Names}
\begin{beschreibung}
 \befehl{D} \iupac{\D}
 \befehl{L} \iupac{\L}
\end{beschreibung}
Since the command \cmd{L} has another meaning already (\L) it is only available
inside \cmd{iupac} in the default setting.

\paragraph{cis/trans, zusammen/entgegen, syn/anti \& tert}\index{tert}\secidx[tert]{IUPAC Names}\index{cis/trans}\secidx[cis/trans]{IUPAC Names}\index{zusammen/entgegen}\secidx[zusammen/entgegen]{IUPAC Names}\secidx[syn/anti]{IUPAC Names}
\begin{beschreibung}
 \befehl{cis} \cis
 \befehl{trans} \trans
 \befehl{Z} \Z
 \befehl{E} \E
 \befehl{syn} \syn
 \befehl{anti} \anti
 \befehl{tert} \tert
\end{beschreibung}
The package \paket{cool} defines the commands \cmd{E} and \cmd{D}, too. If you
load it, the \chemmacros version will only be available inside \cmd{iupac} in
the default setting.

\paragraph{ortho/meta/para}\index{ortho/meta/para}\secidx[ortho/meta/para]{IUPAC Names}
\begin{beschreibung}
 \befehl{ortho} \ortho
 \befehl{meta} \meta
 \befehl{para} \para
\end{beschreibung}

\paragraph{Absolute Configuration}\index{absolute configuration} (uses \TikZ)
\begin{beschreibung}
 \befehl{Rconf}[<letter>] \cmd{Rconf}: \Rconf \quad\cmd{Rconf}[]: \Rconf[]
 \befehl{Sconf}[<letter>] \cmd{Sconf}: \Sconf \quad\cmd{Sconf}[]: \Sconf[]
\end{beschreibung}

Examples:
\begin{beispiel}
 \iupac{\D\-Wein\|s\"aure} = \\
 \iupac{\cip{2S,3S}\-Wein\|s\"aure} \\
 \iupac{\D\-($-$)\-Threose} = \\
 \iupac{\cip{2S,3R}\-($-$)\-2,3,4\-Tri\|hydroxy\|butanal} \\
 \iupac{\cis\-2\-Butene} = \\
 \iupac{\Z\-2\-Butene}, \\
 \iupac{\cip{2E,4Z}\-Hexa\|diene} \\
 \iupac{\meta\-Xylol} = \\
 \iupac{1,3\-Di\|methyl\|benzene}
\end{beispiel}
\secidx*{Stereo Descriptors and Nomenclature}

\paragraph{Coordination Chemistry}
\chemmacros provides two commands useful with coordination chemistry:
\begin{beschreibung}
 \befehl{bridge}{<num>} \bridge{3}
 \befehl{hapto}{<num>} \hapto{5}
\end{beschreibung}
\begin{beispiel}
 Ferrocene = \iupac{bis(\hapto{5}cyclo\|penta\|dienyl)iron} \\
 \iupac{tetra\-\bridge{3}iodido\-tetrakis[tri\|methyl\|platinum(IV)]}
\end{beispiel}

Two options allow customization:
\begin{beschreibung}
 \option[iupac]{bridge-number}{sub|super} appends the number as a subscript or
   superscript. \ac{iupac} recommendation is the subscript \cite{iupac:redbook}.
   Default = \code{sub}
 \option[iupac]{coord-use-hyphen}{\default{true}|false} append a hyphen to
   \cmd{hapto} and \cmd{bridge} or don't. Default = \code{true}
\end{beschreibung}

\subsubsection{Own Naming Commands}\secidx[own]{IUPAC Names}
If you find any commands missing you can define them using
\begin{beschreibung}
 \befehl{DeclareChemIUPAC}{<cmd>}\ma{<declaration>}
 \befehl{RenewChemIUPAC}{<cmd>}\ma{<declaration>}
\end{beschreibung}
A command defined in this way will obey the setting of the option \key[option]{iupac}.
This means any existing command is only overwritten with \key{iupac}{strict}. However,
\cmd{DeclareChemIUPAC} will \emph{not} change the definition of an existing \ac{iupac}
naming command but issue a warning/an error (depending on the package option
\key{strict}) if the \ac{iupac} naming command already exists.
\begin{beispiel}
 \DeclareChemIUPAC\endo{\textit{endo}}
 \RenewChemIUPAC\anti{\textit{anti}}
 \iupac{(2\-\endo,7\-\anti)\-2\-bromo\-7\-fluoro\|bicyclo[2.2.1]heptane}
\end{beispiel}

\cmd{RenewChemIUPAC} allows you to redefine the existing \ac{iupac} naming commands.
\begin{beispiel}
 \iupac{\meta\-Xylol} \\
 \RenewChemIUPAC\meta{\textit{m}}
 \iupac{\meta\-Xylol}
\end{beispiel}

\secidx*{IUPAC Names}

\subsection{Latin Phrases}\secidx{Latin Phrases}
The package \paket{chemstyle} provides the command \cmd{latin} to typeset common
latin phrases in a consistent way. \chemmacros defines a similar \cmd{latin} only
if \paket{chemstyle} has \emph{not} been loaded and additionally provides these
commands:
\begin{beschreibung}
 \befehl{insitu} \insitu
 \befehl{abinitio} \abinitio
 \befehl{invacuo} \invacuo
\end{beschreibung}

If the package \paket{chemstyle} has been loaded they are defined using
\paket{chemstyle}'s \cmd{latin} command. This means that then the appearance
depends on \paket{chemstyle}'s option \code{abbremph}.

The commands are defined through
\begin{beschreibung}
 \Befehl{DeclareChemLatin}{<cmd>}\ma{<phrase>}
 \Befehl{RenewChemLatin}{<cmd>}\ma{<phrase>}
\end{beschreibung}
\begin{beispiel}
 \DeclareChemLatin\ltn{latin text}
 \ltn
\end{beispiel}
If you have \emph{not} loaded \paket{chemstyle} you can change the appearance with
this option:
\begin{beschreibung}
 \option[latin]{format}{<definition>} Default = \lstinline+\itshape+
\end{beschreibung}
\secidx*{Latin Phrases}

\section{Units for the Usage With \textsf{siunitx}}\label{sec:einheiten}\secidx{Units}
In chemistry some non-SI units are very common. \paket{siunitx} provides the
command \lstinline+\DeclareSIUnit{<command>}{<unit>}+ to add arbitrary units.
\chemmacros uses that command to provide some units. Like all \paket{siunitx}
units they're only valid inside \lstinline+\SI{<num>}{<unit>}+ and \lstinline+\si{<unit>}+.
\begin{beschreibung}
 \befehl{atmosphere} \si{\atmosphere}
 \befehl{atm} \si{\atm}
 \befehl{calory} \si{\calory}
 \befehl{cal} \si{\cal}
 \befehl{cmc} \si{\cmc} The units \cmd{cmc}, \cmd{molar}, and \cmd{Molar} are
   defined by the package \paket{chemstyle} as well. \chemmacros only defines them,
   if \paket{chemstyle} is not loaded.
 \befehl{molar} \si{\molar}
 \befehl{moLar} \si{\moLar}
 \befehl{Molar} \si{\Molar}
 \befehl{MolMass} \si{\MolMass}
 \befehl{normal} \si{\normal}
 \befehl{torr} \si{\torr}
\end{beschreibung}

By the way: \lstinline+\mmHg+ \si{\mmHg} already is defined by \paket{siunitx}
and \paket{chemstyle}
\secidx*{Units}

\section{Acid/Base}\label{sec:saeure_base}\secidx{Acid/Base}
Easy representation of \pH, \pKa \ldots\ (the command \cmd{pKa} depends on the
package option \key[option]{language}).
\begin{beschreibung}
 \befehl{pH} \pH
 \befehl{pOH} \pOH
 \befehl{Ka} \Ka
 \befehl{Kb} \Kb
 \befehl{Kw} \Kw
 \befehl{pKa}[<num>] \cmd{pKa}: \pKa, \cmd{pKa}[1]: \pKa[1]
 \befehl{pKb}[<num>] \cmd{pKb}: \pKb, \cmd{pKb}[1]: \pKb[1]
 \befehl{p}{<anything>} \eg \cmd{p}{\cmd{Kw}} \p{\Kw}
\end{beschreibung}

\begin{beispiel}
 \Ka \Kb \pKa \pKa[1] \pKb \pKb[1]
\end{beispiel}

\achtung{The default appearance of the \p{}-commands has changed to follow \ac{iupac}
recommendations.}
\begin{zitat}[{\acs{iupac} Green Book {\cite[][p.\,103]{iupac:greenbook}}}]
 The operator \p{} \textelp{} shall be printed in Roman type.
\end{zitat}

There is one option which changes the style the \p{} is typeset:
\begin{beschreibung}
 \option[acid-base]{p-style}{italics|slanted|upright} Default = \code{upright}
\end{beschreibung}
\begin{beispiel}
 \pH, \pKa

 \chemsetup[acid-base]{p-style=slanted} \pH, \pKa
 
 \chemsetup[acid-base]{p-style=italics} \pH, \pKa
\end{beispiel}
\secidx*{Acid/Base}

\section{Oxidation Numbers, Real and Formal Charges}\label{sec:ladungen}
\chemmacros distinguishes between real ($+$/$-$) and formal (\fplus/\fminus)
charge symbols, also see section~\ref{sec:optionen}. All commands using formal
charge symbols start with a \code{f}.
\subsection{Ion Charges}\label{ssec:ionen}\secidx{Ion Charges}
Simple displaying of (real) charges:
\begin{beschreibung}
 \befehl{pch}[<number>] positive charge (\textbf{p}lus + \textbf{ch}arge)
 \befehl{mch}[<number>] negative charge (\textbf{m}inus + \textbf{ch}arge)
\end{beschreibung}

\begin{beispiel}
 \pch, Na\pch, Ca\pch[2]\\
 \mch, F\mch, S\mch[2]
\end{beispiel}

The same for formal charges:
\begin{beschreibung}
 \befehl{fpch}[<number>] positive charge
 \befehl{fmch}[<number>] negative charge
\end{beschreibung}

\begin{beispiel}
 \fpch\ \fmch\ \fpch[3] \fmch[3]
\end{beispiel}

There is a key which influences the behaviour of the charges.
\begin{beschreibung}
 \option[charges]{append}{\default{true}|false} if set \code{true}, the charge
   is appended together with an empty group. 
\end{beschreibung}
This is how the key influences the behaviour:
\begin{beispiel}
 % uses package `mhchem'
 \chemsetup{charges/append=false,phases/pos=sub}
 \ce{H\pch\aq} \ce{H\aq\pch}

 \chemsetup[charges]{append=true}
 \ce{H\pch\aq} \ce{H\aq\pch}
\end{beispiel}
In most cases this behaviour will be unwanted. However, in some cases it might be
useful, for example together with the \cmd{ox} command (see next section):
\begin{beispiel}
 \chemsetup{charges/append=false,phases/pos=sub}
 \ce{\ox{1,H}\pch\aq}

 \chemsetup[charges]{append=true}
 \ce{\ox{1,H}\pch\aq}
\end{beispiel}
\secidx*{Ion Charges}

\subsection{Oxidation Numbers}\label{ssec:oxidationszahlen}\secidx{Oxidation Numbers}
Typesetting oxidation numbers:
\begin{beschreibung}
 \befehl{ox}[<keyval>]{<number>,<atom>} places \code{<number>} above \code{<atom>};
   \code{<number>} has to be a (rational) number!
\end{beschreibung}

\begin{beispiel}
 \ox{+1,Na}, \ox{2,Ca}, \ox{-2,S}, \ox{-1,F}
\end{beispiel}

There are a number of keys, that can be used to modify the \cmd{ox} command.
\begin{beschreibung}
 \option[ox]{parse}{\default{true}|false} when \code{false} an arbitrary entry
   can be used for \code{<number>}. Default = \code{true}
 \option[ox]{roman}{\default{true}|false} switches from roman to arabic numbers.
   Default = \code{true}
 \option[ox]{pos}{top|super|side}; \code{top} places \code{<number>} above
   \code{<atom>}, \code{super} to the upper right as superscript and \code{side}
   to the right and inside brackets. Default = \code{top}
 \option[ox]{explicit-sign}{\default{true}|false} shows the $+$ for positiv
   numbers and the $\pm$ for $0$. Default = \code{false}
 \option[ox]{decimal-marker}{comma|point} choice for the decimal marker for
   formal oxidation numbers like \ox{1.2,X}. Default = \code{point}
 \option[ox]{align}{center|right} center the oxidation number relative to the atom
  or right-align it. Default = \code{center}
\end{beschreibung}

\begin{beispiel}
 \ox[roman=false]{2,Ca} \ox{2,Ca} \\
 \ox[pos=super]{3,Fe}-Oxide \\
 \ox[pos=side]{3,Fe}-Oxide \\
 \ox[parse=false]{?,Mn} \\
 \ox[align=right]{2,Ca}
\end{beispiel}

The \key[ox]{pos}{super} variant also can be set with the shortcut \cmd{ox}*:
\begin{beispiel}
 \ox{3,Fe} \ox*{3,Fe}
\end{beispiel}

Using the \key[ox]{explicit-sign} key will always show the sign of the oxidation
number:
\begin{beispiel}
 \chemsetup[ox]{explicit-sign = true}
 \ox{+1,Na}, \ox{2,Ca}, \ox{-2,S}, \ch{"\ox{0,F}" {}2}
\end{beispiel}

\begin{beispiel}
 Compare \ox{-1,\ch{O2^2-}} to \ch{"\ox{-1,O}" {}2^2-}
\end{beispiel}

Sometimes one might want to use formal oxidation numbers like \num{.5} or $\frac{1}{3}$:
\begin{beispiel}
 \ox{.5,\ch{Br2}} \ch{"\ox{1/3,I}" {}3+}
\end{beispiel}

The fraction uses the \lstinline+\sfrac+ command of the \paket{xfrac} package.
For this purpose the instance \lstinline+chemmacros-ox-frac+ is defined.
\begin{beispiel}[code only]
\DeclareInstance{xfrac}{chemmacros-ox-frac}{text}
  {
    scale-factor        = 1.2 ,
    denominator-bot-sep = -.5ex ,
    numerator-top-sep   = -.3ex ,
    slash-left-kern     = -.2em ,
    slash-right-kern    = -.2em ,
    slash-symbol-font   = lmr
  }
\end{beispiel}
Of course you can redefine it so that it suits your needs as the output often
strongly depends on the used font.
\secidx*{Oxidation Numbers}

\subsection{Partial Charges and Similar Stuff}\label{ssec:partialladungen}\secidx{Partial Charges}
The next ones probably are seldomly needed but nevertheless useful:
\begin{beschreibung}
 \befehl{delp} \delp\ (\textbf{del}ta + \textbf{p}lus)
 \befehl{delm} \delm\ (\textbf{del}ta + \textbf{m}inus)
 \befehl{fdelp} \fdelp
 \befehl{fdelm} \fdelm
\end{beschreibung}

These macros for example can be used with the \cmd{ox} command or with the
\paket{chemfig} package:
\begin{beispiel}
 \chemsetup{
   option/circled = all,
   ox/parse       = false
 }
 \ce{\ox{\delp,H}-\ox{\delm,Cl}} \hspace*{1cm}
 \chemfig{\chemabove[3pt]{\lewis{246,Br}}{\delm}-\chemabove[3pt]{H}{\delp}}
\end{beispiel}

The following macros are useful together with \paket{chemfig}, too.
\begin{beschreibung}
 \befehl{scrp} \scrp\ (\textbf{scr}iptstyle + \textbf{p}lus)
 \befehl{scrm} \scrm\ (\textbf{scr}iptstyle + \textbf{m}inus)
 \befehl{fscrp} \fscrp
 \befehl{fscrm} \fscrm
 \befehl{fsscrp} \fsscrp\ (using \lstinline+\scriptscriptstyle+)
 \befehl{fsscrm} \fsscrm
\end{beschreibung}

\begin{beispiel}
 \setatomsep{1.8em}\chemfig{CH_3-\chemabove{C}{\scrp}(-[6]C|H_3)-\vphantom{H_3}CH_3}
 
 \chemfig{\fmch{}|O-\chemabove{N}{\fscrp}(-[1]O|\fmch)-[7]O|\fmch}
\end{beispiel}
\secidx*{Partial Charges}

\section{Reaction Mechanisms}\label{sec:mechanismen}\secidx{Reaction Mechanisms}
With the command
\begin{beschreibung}
 \Befehl{mech}[<type>]
\end{beschreibung}
one can specify the most common reaction mechanisms. \code{<type>} can have one
of the following values:
\begin{beschreibung}
 \befehl{mech} (empty, no opt. argument) nucleophilic substitution \mech
 \befehl{mech}[1] unimolecular nucleophilic substitution \mech[1]
 \befehl{mech}[2] bimolecular nucleophilic substitution \mech[2]
 \befehl{mech}[se] electrophilic substitution \mech[se]
 \befehl{mech}[1e] unimolecular electrophilic substitution \mech[1e]
 \befehl{mech}[2e] bimolecular electrophilic substitution \mech[2e]
 \befehl{mech}[ar] electrophilic aromatic substitution \mech[ar]
 \befehl{mech}[e] elimination \mech[e]
 \befehl{mech}[e1] unimolecular elimination \mech[e1]
 \befehl{mech}[e2] bimolecular elimination \mech[e2]
 \befehl{mech}[cb] unimolecular elimination \enquote{conjugated base}, \ie via
   carbanion \mech[cb]
\end{beschreibung}
\secidx*{Reaction Mechanisms}

\section{Redox Reactions}\label{sec:redoxreaktionen}\secidx{Redox Reactions}% TODO: watch pagebreaks!
\chemmacros provides two commands to visualize the transfer of electrons in redox
reactions. Both commands are using \TikZ.
\begin{beschreibung}
 \Befehl{OX}{<name>,<atom>}
 \Befehl{redox}(<name1>,<name2>)[<tikz>]\oa{<num>}{<text>} \cnpkgdocarrow\ Only
 the first argument \da{<name1>,<name2>} is required, the others are all optional.
\end{beschreibung}

\cmd{OX} places \code{<atom>} into a node, which is named with \code{<name>}. If
you have set two \cmd{OX}, they can be connected with a line using \cmd{redox}.
To do so the names of the two nodes that are to be connected are written in the
round braces. Since \cmd{redox} draws a tikzpicture with options \code{remember
picture,overlay}, the document needs to be \emph{compiled at least two times}.
\begin{beispiel}[dist]
 \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b){oxidation}
\end{beispiel}
This line can be customized using \TikZ keys in \oa{<tikz>}:
\begin{beispiel}[ox]
 \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
\end{beispiel}

With the argument \oa{<num>} the length of the vertical parts of the line can be
adjusted. The default length is \code{.6em}. This length is multiplied with
\code{<num>}. If you use a negative value the line is placed  \emph{below} the
text.
\begin{beispiel}[dist]
 \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch
 \redox(a,b)[->,red]{ox}
 \redox(a,b)[<-,blue][-1]{red}
 \vspace{7mm}
\end{beispiel}
The default length of the vertical lines can be customized with the option
\begin{beschreibung}
 \option[redox]{dist}{<dim>} A \TeX\ dimension. Default = \code{.6em}
\end{beschreibung}
\begin{beispiel}[dist]
 \chemsetup{redox/dist=1em}
 \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
\end{beispiel}

Additionally the option
\begin{beschreibung}
 \option[redox]{sep}{<dim>} Default = \code{.2em}
\end{beschreibung}
can be used to change the distance between the atom and the beginning of the line.
\begin{beispiel}[dist]
 \chemsetup{redox/sep=.5em}
 \OX{a,Na} $\rightarrow$ \OX{b,Na}\pch\redox(a,b)[->,red]{ox}
\end{beispiel}

Examples:% TODO: watch pagebreaks!
\begin{beispiel}[dist]
 \ch{ 2 "\OX{o1,Na}" + "\OX{r1,Cl}" {}2 -> 2 "\OX{o2,Na}" \pch{} + 2
"\OX{r2,Cl}" \mch }
 \redox(o1,o2){\small OX: $- 2\el$}
 \redox(r1,r2)[][-1]{\small RED: $+ 2\el$}
 \vspace{7mm}
\end{beispiel}
\begin{beispiel}[dist]
 \ch{ 2 "\OX{o1,\ox{0,Na}}" + "\OX{r1,\ox{0,Cl}}" {}2 -> 2 "\OX{o2,\ox{+1,Na}}"
\pch{} + 2 "\OX{r2,\ox{-1,Cl}}" \mch }
 \redox(o1,o2){\small OX: $- 2\el$}
 \redox(r1,r2)[][-1]{\small RED: $+ 2\el$}
 \vspace{7mm}
\end{beispiel}
\bspmidlength{dist}{15mm}
\begin{beispiel}[dist]
 \ch{ 2 "\OX{o1,\ox{0,Na}}" + "\OX{r1,\ox{0,Cl}}" {}2 -> 2 "\OX{o2,\ox{+1,Na}}"
\pch{} + 2 "\OX{r2,\ox{-1,Cl}}" \mch }
 \redox(o1,o2)[draw=red,->][3.33]{\small OX: $- 2\el$}
 \redox(r1,r2)[draw=blue,->]{\small RED: $+ 2\el$}
\end{beispiel}

\newpage
\bspmidlength{dist}{7mm}
 \begin{beispiel}[dist]
 \ch{ 2 "\OX{o1,\ox{0,Na}}" + "\OX{r1,\ox{0,Cl}}" {}2 -> 2 "\OX{o2,\ox{+1,Na}}"
\pch{} + 2 "\OX{r2,\ox{-1,Cl}}" \mch }
 \redox(o1,o2)[green,-stealth]{\small OX}
 \redox(r1,r2)[purple,-stealth][-1]{\small RED}
 \vspace{7mm}
\end{beispiel}
\secidx*{Redox Reactions}

\section{(Standard) State, Thermodynamics}\label{sec:standardstate}\secidx{Thermodynamics}
\subsection{Thermodynamic Variables}\label{ssec:siunitx}
The following commands use \paket{siunitx}:
\begin{beschreibung}
 \Befehl{Enthalpy}[<keyval>]\da{<subscript>}\ma{<value>}
 \Befehl{Entropy}[<keyval>]\da{<subscript>}\ma{<value>}
 \Befehl{Gibbs}[<keyval>]\da{<subscript>}\ma{<value>}
\end{beschreibung}

Their usage is pretty much self-explaining:
\begin{beispiel}
  \Enthalpy{123} \\
  \Entropy{123} \\
  \Gibbs{123}
\end{beispiel}
The argument \da{<subscript>} adds a subscript for specification:
\cmd{Enthalpy}(r){123} \Enthalpy(r){123}.

There are several keys to customize the commands.
\begin{beschreibung}
 \Option*{exponent}{<anything>}
 \Option*{delta}{<anything>|false}
 \Option*{subscript}{left|right}
 \Option*{unit}{<unit>}
\end{beschreibung}

The default values depend on the command.
\begin{beispiel}
 \Enthalpy[unit=\kilo\joule]{-285} \\
 \Gibbs[delta=false]{0} \\
 \Entropy[delta=\Delta,exponent=]{56.7}
\end{beispiel}
The unit is set corresponding to the rules of \paket{siunitx} and depends on its
settings:
\begin{beispiel}
 \Enthalpy{-1234.56e3} \\
 \sisetup{per-mode=symbol,exponent-product=\cdot,output-decimal-marker={,},group-four-digits=true}
 \Enthalpy{-1234.56e3}
\end{beispiel}

\subsubsection{Create New Variables}
You can use the command
\begin{beschreibung}
 \Befehl{DeclareChemState}[<keyval>]{<name>}\ma{<symbol>}\ma{<unit>}
\end{beschreibung}

to create new corresponding commands:
\begin{beispiel}
 \DeclareChemState{Helmholtz}{A}{\kilo\joule\per\mole}
 \DeclareChemState[subscript-left=false,exponent=]{ElPot}{E}{\volt}
 \Helmholtz{123.4} \\
 \ElPot{-1.1} \\
 \ElPot[exponent=0]($\ch{Sn}|\ch{Sn^2+}||\ch{Pb^2+}|\ch{Pb}$){0.01}
\end{beispiel}

The command has some keys with which the default behaviour of the new command can
be set.
\begin{beschreibung}
 \Option*{exponent}{<anything>}
 \Option*{delta}{<anything>|false}
 \Option*{subscript-left}{\default{true}|false}
 \Option*{subscript}{<anything>}
\end{beschreibung}

\subsubsection{Redefine Variables}
With
\begin{beschreibung}
 \Befehl{RenewChemState}[<keyval>]{<name>}\ma{<symbol>}\ma{<unit>}
\end{beschreibung}

you can redefine the already existing commands:
\begin{beispiel}
 \RenewChemState{Enthalpy}{h}{\joule}
 \Enthalpy(f){12.5}
\end{beispiel}
The command is analogous to \cmd{DeclareChemState}, \ie it has the same keys.

So \textendash\ for following thermodynamic conventions \textendash\ one could
define a molar and an absolute variable:
\begin{beispiel}
 \DeclareChemState[exponent=]{enthalpy}{h}{\kilo\joule\per\mole}% molar
 \RenewChemState[exponent=]{Enthalpy}{H}{\kilo\joule}% absolute
 \enthalpy{-12.3} \Enthalpy{-12.3}
\end{beispiel}

\subsection{State}\label{ssec:state}
The commands presented in section~\ref{ssec:siunitx} internally all use the
command\footnote{Please note that \ma{<subscript>} is an \emph{optional} argument.}
\begin{beschreibung}
 \Befehl{State}[<keyval>]{<symbol>}\ma{<subscript>}
\end{beschreibung}

It can be used to write the thermodynamic variables without value and unit.

Examples:
\begin{beispiel}
 \State{A}, \State{G}{f}, \State[subscript-left=false]{E}{\ch{Na}}, \State[exponent=\SI{1000}{\celsius}]{H}
\end{beispiel}

Again there are some keys to customize the command:
\begin{beschreibung}
 \Option[state]{exponent}{<anything>}
 \Option[state]{subscript-left}{\default{true}|false}
 \Option[state]{delta}{<anything>|false}
\end{beschreibung}
\secidx*{Thermodynamics}

\section{Spectroscopy and Experimental Data}\label{sec:spektroskopie}\secidx{Spectroscopy}
\subsection{The \code{\textbackslash\textcolor{code}{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}
\chemmacros provides a command which simplifies the input (uses \paket{siunitx}).

\begin{beschreibung}
 \Befehl{NMR}*{<num>,<elem>}\da{<num>,<unit>}\oa{<solvent>}
\end{beschreibung}

\emph{All} Argument are optional! Without arguments we get:
\begin{beispiel}
 \NMR \\
 \NMR*
\end{beispiel}

The first argument specifies the kind of NMR:
\begin{beispiel}
 \NMR{13,C}
\end{beispiel}

The second argument sets the frequency (in \si{\mega\hertz}):
\begin{beispiel}
 \NMR(400)
\end{beispiel}
You can choose another unit:
\begin{beispiel}
 \NMR(4e8,\hertz)
\end{beispiel}
Please note that the setup of \paket{siunitx} also affects this command:
\begin{beispiel}
 \sisetup{exponent-product=\cdot}\NMR(4e8,\hertz)
\end{beispiel}

The third argument specifies the solvent:
\begin{beispiel}
 \NMR[CDCl3]
\end{beispiel}

\subsection{Short Cuts}
It is possible to define short cut commands for specific nuclei.
\begin{beschreibung}
 \Befehl{DeclareChemNMR}{<csname>}\ma{<num>,<atom>}
 \Befehl{RenewChemNMR}{<csname>}\ma{<num>,<atom>}
\end{beschreibung}
This defines a command with the same arguments as \cmd{NMR} \emph{except} for
\ma{<num>,<atom>}.
\begin{beispiel}
 \DeclareChemNMR\HNMR{1,H}%
 \DeclareChemNMR\CNMR{13,C}%
 \CNMR*(100) \\
 \HNMR*(400)
\end{beispiel}

\subsection{An Environment to Typeset Experimental Data}
\chemmacros provides an environment to ease the input of experimental data.
\begin{beschreibung}\catcode`\#=11
 \umg{experimental}{data} Environment for the output of experimental data. Inside
   the environment the following commands are defined.
 \Befehl{data}{<type>}\oa{<specification>} \cnpkgdocarrow\ Type of data, \eg\ IR,
   MS\ldots\ The optional argument takes further specifications which are output
   in parentheses.
 \Befehl{data}*{<type>}\oa{<specification>} \cnpkgdocarrow\ Like \cmd{data} but
   changes the \code{=} into a \code{:}, given that \key{use-equal}{true} is used.
  \Befehl{NMR}{<num>,<elem>\oa{<coupling core>}}\da{<num>,<unit>}\oa{<solvent>}
   \cnpkgdocarrow\ this command gets an additional argument:
   \cmd{NMR}{13,C[\textasciicircum 1H]} \NMR{13,C[^1H]}
 \Befehl{J}\da{<bonds>;<nuclei>}\oa{<unit>}\ma{<list of nums>} \cnpkgdocarrow\
   Coupling constant, values are input separated by \code{;} (NMR). The argument
   \da{<bonds>;<nuclei>} is optional and enables further specifications of the
   coupling.
 \befehl{#}{<num>} Number of nuclei (NMR).
 \befehl{pos}{<num>} Position of nuclues (NMR).
 \befehl{val}{<num>} A number, an alias of \paket*{siunitx}' \lstinline+\num{<num>}+
 \befehl{val}{<num1>-{}-<num2>} An alias of \paket*{siunitx}' \lstinline+\numrange{<num1>}{<num2>}+
\end{beschreibung}

\begin{beispiel}
 \begin{experimental}
  \data{type1} Data.
  \data{type2}[specifications] More data.
  \data*{type3} Even more data.
 \end{experimental}
\end{beispiel}

\subsection{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
\textcolor{module}{\code{nmr}}.
\begin{beschreibung}
 \option[nmr]{unit}{<unit>} Default = \lstinline=\mega\hertz=
 \option[nmr]{nucleus}{\{<num>,<atom>\}} Default = \ma{1,H}
 \option[nmr]{format}{<commands>} for example \lstinline=\bfseries=
 \option[nmr]{pos-number}{side|sub} Position of the number next to the atom.
   Default = \code{side}
 \option[nmr]{coupling-unit}{<unit>} A \paket{siunitx} unit. Default =
   \lstinline=\hertz=
 \option[nmr]{parse}{\default{true}|false} Treat the solvent as \paket{mhchem}/\chemformula
   formula or not. Default = \code{true}
 \option[nmr]{delta}{<tokens>} The \code{<tokens>} are added after $\delta$.
 \option[nmr]{list}{\default{true}|false} The environment \env{nmr}[<optionen>]{} is
   formatted as a list. Default = \code{false}
 \option[nmr]{list-setup}{<setup>} Setup of the list. Default =  see below.
 \option[nmr]{use-equal}{\default{true}|false} Add egual sign after \cmd{NMR}
   and \cmd{data}. Default = \code{false}
\end{beschreibung}

The default setup of the list:
\begin{beispiel}[code only]
    \topsep\z@skip \partopsep\z@skip 
    \itemsep\z@ \parsep\z@ \itemindent\z@
    \leftmargin\z@
\end{beispiel}

\begin{beispiel}
 \begin{experimental}[format=\bfseries]
  \data{type1} Data.
  \data{type2}[specifications] More data.
  \data*{type3} Even more data.
 \end{experimental}
\end{beispiel}

The command \cmd{NMR} and all commands defined through \cmd{DeclareChemNMR} can
be used like \cmd{data} for the NMR data.

\begin{beispiel}
 \begin{experimental}[format=\bfseries,use-equal]
  \data{type1} Data.
  \data{type2}[specifications] More data.
  \NMR Even more data.
 \end{experimental}
\end{beispiel}

\subsection{An Example}
The code below is shown with different specifications for \code{<optionen>}. Of
course options can also be chosen with \cmd{chemsetup}.

\begin{beispiel}[code only]
\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{beispiel}

\subsubsection{Nearly Standard}
Output with these options: \lstinline+<optionen>: delta=(ppm),pos-number=sub,use-equal+
\bigskip

\begin{experimental}[delta=(ppm),pos-number=sub,use-equal]
 \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
 \chemsetup[chemformula]{
   font-spec =
     {[Numbers={Proportional,Lining}]Linux Libertine O}
 }
 %
 \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}

\subsubsection{Formatted List}
Output with these options: \lstinline+<optionen>: format=\bfseries,delta=(ppm),list=true,use-equal+
\bigskip

\begin{experimental}[format=\bfseries,delta=(ppm),list=true,use-equal]
 \sisetup{separate-uncertainty,per-mode=symbol,detect-all,range-phrase=--}
 \chemsetup[chemformula]{
   font-spec =
     {[Numbers={Proportional,Lining}]Linux Libertine O}
 }
 %
 \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}

\subsubsection{Crazy}
Output for these options: \code{<optionen>}:
\begin{lstlisting}
  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{lstlisting}

\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=--}
 \chemsetup[chemformula]{
   font-spec =
     {[Numbers={Proportional,Lining}]Linux Libertine O}
 }
 %
 \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}
\secidx*{Spectroscopy}

\section{Commands for \textsf{mhchem}}\label{sec:mhchem}\secidx{Commands for mhchem}
\paket{mhchem} isn't loaded automatically any more but only if you've specified
\key[option]{method}{mhchem} in the preamble. In the default settings \chemmacros
uses \chemformula instead.

\chemmacros provides only one command specifically for \paket*{mhchem}%
\footnote{\chemformula provides its own possibility.}. It is meant to place text
below of compounds.
\begin{beschreibung}
 \Befehl{mhName}[<keyval>]{<formula>}\ma{<text>}
\end{beschreibung}

For example:
\begin{beispiel}
 \ce{4 C2H5Cl + Pb / Na -> \mhName{Pb(C2H5)4}{former antiknock additive} + NaCl}
\end{beispiel}

There are several keys to customize \cmd{mhName}.
\begin{beschreibung}
 \option[mhName]{align}{<alignment command>} the alignment of the text in the box
   it is placed in, default = \lstinline+\centering+
 \option[mhName]{format}{<anything>} the format of the text
 \option[mhName]{fontsize}{<font size command>} the fontsize of the text, default
   = \lstinline+\tiny+
 \option[mhName]{width}{<dim>|auto} the width of the box the text is placed in,
   default = \code{auto}
\end{beschreibung}
\begin{beispiel}
 \ce{4 C2H5Cl + Pb / Na -> \mhName[fontsize=\footnotesize]{Pb(C2H5)4}{former antiknock additive} + NaCl}\\
 \chemsetup[mhName]{align=\raggedright,fontsize=\small,format=\bfseries\color{red},width=3cm}
 \ce{4 C2H5Cl + Pb / Na -> \mhName{Pb(C2H5)4}{former antiknock additive} + NaCl}
\end{beispiel}
\secidx*{Commands for mhchem}

\section{Reaction Environments}\label{sec:reactions}\secidx{Reaction Environments}
\subsection{Defined by \chemmacros}
You can use these environments for numbered\ldots
\begin{beschreibung}
 \Umg{reaction}{<formula or mhchem code>}
 \Umg{reactions}{<formula or mhchem code>}
\end{beschreibung}

\ldots and their starred versions for unnumbered reactions.
\begin{beschreibung}
 \Umg{reaction*}{<formula or mhchem code>}
 \Umg{reactions*}{<formula or mhchem code>}
\end{beschreibung}

With them you can create (un)numbered reaction equations similar to mathematical
equations.

Theses environments use the \code{equation}/\code{equation*} environments or the
\code{align}/\code{align*} environments, respectively, to display the reactions.

\begin{beispiel}
 Reaction with counter:
 \begin{reaction}
  A -> B
 \end{reaction}
\end{beispiel}

\begin{beispiel}
 Reaction without counter:
 \begin{reaction*}
  C -> D
 \end{reaction*}
\end{beispiel}

\begin{beispiel}
 Several aligned reactions with counter:
 \begin{reactions}
  A     &-> B + C \\
  D + E &-> F
 \end{reactions}
\end{beispiel}

\begin{beispiel}
 Several aligned reactions without counter:
 \begin{reactions*}
  G     &-> H + I \\
  J + K &-> L
 \end{reactions*}
\end{beispiel}

If you want to change the layout of the counter tags, you can use

\cmd{renewtagform}{<tagname>}\oa{<format>}\ma{<right delim>}\ma{<left delim>}%
\footnote{Provided by the \paket*{mathtools} package}.

\begin{beispiel}
 \renewtagform{reaction}[R \textbf]{[}{]}
 \begin{reaction}
  H2O + CO2 <<=> H2CO3
 \end{reaction}
\end{beispiel}

With version 3.3 referencing and the use of \AmS math's \cmd{intertext} also
function properly:
\begin{beispiel}
 \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{beispiel}

\achtung{In the standard setting, \ie using \key{method}{chemformula} you should
not use \cmd{mch} and its relatives inside the \code{reaction} environments. They
will very likely mess with spacing. In the standard setting charges inside the
environments automatically recognize the setting of the option \key{circled} so
there's also no need for the charge commands.}

\subsection{Own Reactions}
You can create new types of reactions with the command:
\begin{beschreibung}
 \Befehl{DeclareChemReaction}[<keyval>]{<name>}\ma{<math name>}
\end{beschreibung}

\code{<name>} will be the name of the new environment. \code{<math name>} is the
used math environment.

The command has two options.
\begin{beschreibung}
 \Option*{star}{\default{true}|false}
 \Option*{arg}{\default{true}|false}
\end{beschreibung}
There is \key*{star}, which will also define a starred version of the new
environment, if the starred math environment exists. If it doesn't exist, this
will cause an error.

Then there is \key*{arg}, which is used to define an environment with a mandatory
argument. Of course this only works, if the used math environment has a mandatory
argument.

The predefined environments are defined via
\begin{beschreibung}
 \Befehl{DeclareChemReaction}[star]{reaction}\ma{equation} and
 \Befehl{DeclareChemReaction}[star]{reactions}\ma{align}.
\end{beschreibung}

Let's suppose, you'd like to have the alignment behaviour of the \code{alignat}
environment for \chemformula/\paket{mhchem} reactions. You could do the following:

\cmd{DeclareChemReaction}[star,arg]{reactionsat}\ma{alignat}

With this the \code{reactionsat} environment is defined.
\begin{beispiel}
 \DeclareChemReaction[star,arg]{reactionsat}{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{beispiel}

\subsection{List of Reactions}
\chemmacros also provides a command to display a list of the reactions created
with the \lstinline+reaction+ environment.
\begin{beschreibung}
 \Befehl{listofreactions}
\end{beschreibung}
\begin{beispiel}[below]
 \listofreactions
\end{beispiel}

The Output of this list can be modified by two options:
\begin{beschreibung}
 \option[reaction]{list-name}{<name of the list>} Let's you set the name of the
   list manually. Default = \code{List of reactions}
 \option[reaction]{list-entry}{<prefix to each entry>} Let's you set a prefix to
   each list entry. Default = \code{Reaction}
\end{beschreibung}
Both default option values recognize the package option \key[option]{german}.

Instead of using the option \key{list-name} you also could redefine \cmd{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{beispiel}
 \begin{reaction}[Autoprotolyse]
  2 H2O <<=> H3O+ + OH-
 \end{reaction}
\end{beispiel}
If you use the \code{reactions} environment this will not work, though. In this
case you can use
\begin{beschreibung}
 \Befehl{AddRxnDesc}{<description>}
\end{beschreibung}
\begin{beispiel}
 \begin{reactions}
  Cl "\Lewis{0.,\vphantom{Cl}}" + CH4    &-> HCl + "\Lewis{4.,\vphantom{CH}}" CH3 \AddRxnDesc{first~step~of~chain} \\
  "\Lewis{4.,\vphantom{CH}}" CH3 + Cl2 &-> CH3Cl + Cl "\Lewis{0.,\vphantom{Cl}}" \AddRxnDesc{second~step~of~chain}
 \end{reactions}
\end{beispiel}
Note: you don't have to use the phantom commands if you haven't changed the format
of the atoms, see section~\ref{sec:format} on page~\pageref{sec:format}.
\secidx*{Reaction Environments}

\section{Phases}\label{sec:phasen}\secidx{Phases}
\subsection{Basics}\secidx[basics]{Phases}
These commands are intended to indicate the phase of a compound.
\begin{beschreibung}
 \befehl{sld} \sld
 \befehl{lqd} \lqd
 \befehl{gas} \gas
 \befehl{aq} \aq
\end{beschreibung}

\achtung{The default behaviour of the phases commands has changed to be consistent
with \ac{iupac} recommendations. Both \cmd{sld} and \cmd{lqd} have lost their optional
argument.}

\begin{beispiel}
 \ch{C\sld{} + 2 H2O\lqd{} -> CO2\gas{} + 2 H2\gas}\\
 To make it complete: NaCl\aq.
\end{beispiel}

With the package option \key{language}{german} (see section~\ref{sec:optionen})
you get the german versions.

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{zitat}[{\acs{iupac} Green Book {\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{zitat}

There are two options to customize the output:
\begin{beschreibung}
 \option[phases]{pos}{side|sub} Switch the position of the phase indicator.
   Default = \code{side}
 \option[phases]{space}{<dim>} Change the default spacing between compound a phase
   indicator if \key{pos}{side}. A \TeX\ dimension. Default = \code{.1333em}
\end{beschreibung}
\begin{beispiel}
 \chemsetup[phases]{pos=sub}
 \ch{C\sld{} + 2 H2O\lqd{} -> CO2\gas{} + 2 H2\gas}\\
 To make it complete: NaCl\aq.
\end{beispiel}

\subsection{Define Own Phases}\secidx[own]{Phases}
Depending on the subject of your document you might need to indicate other states
of aggregation. You can easily define them.
\begin{beschreibung}
 \Befehl{DeclareChemPhase}{<cmd>}\oa{<german>}\ma{<english>}
 \Befehl{RenewChemPhase}{<cmd>}\oa{<german>}\ma{<english>}
 \befehl{phase}{<phase>} If you need a phase indicator just once or twice.
\end{beschreibung}
\cmd{DeclareChemPhase} only defines a phase if \code{<cmd>} is not already used
by any other command. If it \emph{is} already used \chemmacros will either give
a warning or an error, depending on the option \key{strict}. \cmd{RenewChemPhase}
\emph{only} defines a phase if \code{<cmd>} \emph{is} already used and issues a
warning/error otherwise.
\begin{beispiel}
 \DeclareChemPhase{\aqi}{aq,$\infty$}% aqueous solution at infinite dilution
 \DeclareChemPhase{\cd}{cd}% condensed phase
 \RenewChemPhase{\lqd}{lc}% liquid crystal
 NaOH\aqi\ \ch{H2O\cd} U\phase{cr} A\lqd \\
 \chemsetup[phases]{pos=sub}
 NaOH\aqi\ \ch{H2O\cd} U\phase{cr} A\lqd
\end{beispiel}
\secidx*{Phases}

\section{Newman Projections}\label{sec:newman}\secidx{Newman Projections}
\chemmacros provides the command
\begin{beschreibung}
 \Befehl{newman}[<keyval>]\da{<angle>}\ma{<1>,<2>,<3>,<4>,<5>,<6>}
\end{beschreibung}
which allows you to create newman projections (uses \TikZ). With \code{<angle>}
the back atoms are rotated counter clockwise with respect to the front atoms.
\begin{beispiel}
 \newman{} \newman(170){}
 \newman{1,2,3,4,5,6} \newman{1,2,3} \newman{,,,4,5,6}
\end{beispiel}

Several options allow customization:
\begin{beschreibung}
 \option[newman]{angle}{<angle>} default angle
 \option[newman]{scale}{<factor>} scale the whole projection
 \option[newman]{ring}{<tikz>} customize the ring with \TikZ keys
 \option[newman]{atoms}{<tikz>} customize the nodes within which the atoms are set
 \option[newman]{back-atoms}{<tikz>} explicitly customize the back atoms
\end{beschreibung}

\begin{beispiel}
 \chemsetup[newman]{angle=45} \newman{}
 \newman[scale=.75,ring={draw=blue,fill=blue!20}]{}
\end{beispiel}
\begin{beispiel}
 \chemsetup[newman]{atoms={draw=red,fill=red!20,inner sep=2pt,rounded corners}}
 \newman{1,2,3,4,5,6}
\end{beispiel}
\begin{beispiel}
 \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{beispiel}
\secidx*{Newman Projections}

\section{s, p, and Hybrid Orbitals}\label{sec:orbitale}\secidx{Orbitals}
\chemmacros provides the following command to create orbitals:
\begin{beschreibung}
 \Befehl{orbital}[<keyval>]{<type}
\end{beschreibung}

There are the following types available for \code{<type>}:
\begin{description}
 \item \code{s}
 \item \code{p}
 \item \code{sp}
 \item \code{sp2}
 \item \code{sp3}
\end{description}

\begin{beispiel}
 \orbital{s} \orbital{p} \orbital{sp} \orbital{sp2} \orbital{sp3}
\end{beispiel}

Depending on the type you have different options to modify the orbitals:
\begin{beschreibung}
 \option[orbital]{phase}{\default{+}|-} changes the phase of the orbital (all types)
 \option[orbital]{scale}{<factor>} changes the size of the orbital (all types)
 \option[orbital]{color}{<color>} changes the color of the orbital (all types)
 \option[orbital]{angle}{<angle>} rotates the orbitals with a p contribution counter
   clockwise (all types except \code{s})
 \option[orbital]{half}{\default{true}|false} displays only half an orbital (only
   \code{p})
\end{beschreibung}

\begin{beispiel}
 \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{beispiel}

Additionally there are two options, with which the \TikZ behaviour can be changed.
\begin{beschreibung}
 \option[orbital]{overlay}{\default{true}|false} the orbital \enquote{doesn't need
   space}; it is displayed with the \TikZ option \code{overlay}.
 \option[orbital]{opacity}{<num>} the orbital becomes transparent; \code{<value>}
   can have values between \code{1} (fully opaque) to \code{0} (invisible).
\end{beschreibung}
\begin{beispiel}[dist]
 \hspace{1cm}
 \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{beispiel}

\newpage
\bspmidlength{dist}{10mm}
\begin{beispiel}[dist]
 \hspace{2cm}
 \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{beispiel}
\bspmidlength{dist}{7mm}
\secidx*{Orbitals}\secidx*{CHEMMACROS}

\newpage
\part{\texorpdfstring{\Chemformula}{chemformula}}\secidx{CHEMFORMULA}\label{part:chemformula}
\chemsetup[chemformula]{
  font-spec =
    {[Numbers={Proportional,Lining}]Linux Libertine O}
}
\section{Setup}
All of \chemformula's options belong to the module \textcolor{module}{\code{chemformula}}.
This means they can be setup with
\begin{beispiel}[code only]
 \chemsetup[chemformula]{<options>} or
 \chemsetup{chemformula/<option1>,chemformula/<option2>}
\end{beispiel}

\section{The Basic Principle}
\chemformula offers one main command.
\begin{beschreibung}
 \Befehl{ch}[<options>]{<input>}
\end{beschreibung}
The usage will seem very familiar to you if you're familiar with \paket{mhchem}:
\begin{beispiel}
 \ch{H2O} \\
 \ch{Sb2O3} \\
 \ch{H+} \\
 \ch{CrO4^2-} \\
 \ch{AgCl2-} \\
 \ch{[AgCl2]-} \\
 \ch{Y^{99}+} \\
 \ch{Y^{99+}} \\
 \ch{H2_{(aq)}} \\
 \ch{NO3-} \\
 \ch{(NH4)2S} \\
 \ch{^{227}_{90}Th+} \\
 $V_{\ch{H2O}}$ \\
 \ch{Ce^{IV}} \\
 \ch{KCr(SO4)2 * 12 H2O}
\end{beispiel}

However, there are differences. The most notable one: \chemformula distinguishes
between different types of input. These different parts \emph{have} to be seperated
with blanks:
\begin{beschreibung}
 \Befehl{ch}{part1 part2 part3 part4}
\end{beschreibung}
A blank in the input \emph{never} is a blank in the output. This role of the blank
strictly holds and disregarding it can have unexpected results and even lead to errors.

Another notable difference: \chemformula tries to avoid math mode whenever possible:
\begin{beispiel}
 \ch{A + B ->[a] C} \\
 \ce{A + B ->[a] C}
\end{beispiel}

This means that \cmd{ch}{2H2O} is recognized as a \emph{single} part, which in
this case is recognized as a compound.
\begin{beispiel}
 \ch{2H2O} \\
 \ch{2 H2O}
\end{beispiel}
This also means, that a part cannot contain a blank since this will automatically
divide it into two parts. If you need an extra blank in the output you need to use
\lstinline+~+. However, since commands in most cases gobble a space after them a
input like \cmd{ch}{\textbackslash command ABC} will be treated as a single part.
If you want or need to divide them you need to add an empty group:
\cmd{ch}{\textbackslash command\{\} ABC}. The different input types are described
in the following sections.

There are some options to customize the output of the \cmd{ch} command. They can
either be applied locally using the optional argument or can be set globally using
the setup command. All options of \chemformula belong to the module
\textcolor{module}{\code{chemformula}}.
\begin{beschreibung}
 \Befehl{chemsetup}[chemformula]{<options>}
\end{beschreibung}

\section{Stoichiometric Factors}\secidx{Stoichiometric Factors}
A stoichiometric factor may only contain of numbers and the signs \lstinline+.,_/()+
\begin{beispiel}
 \ch{2} \\
 \ch{12}

 % decimals:
 \ch{3.5} \\
 \ch{5,75}

 % fractions:
 \ch{3/2} \\
 \ch{1_1/2}
\end{beispiel}

You have to be a little bit careful with the right syntax but I believe it is
rather intuitive.
\begin{beispiel}[code only]
 this won't work but will result in an error: \ch{1/1_1}
\end{beispiel}

If stoichiometric factors are enclosed with parentheses the fractions are not
recognized. What's inside the parenthesis is typeset as is.
\begin{beispiel}
 \ch{(1/2) H2O} \ch{1/2 H2O} \ch{0.5 H2O}
\end{beispiel}
You can find many examples like the following for stoichiometric factors in
parentheses in the \acs{iupac} Green Book~\cite{iupac:greenbook}:
\begin{reaction*}
 (1/5) K "\ox*{7,Mn}" O4 + (8/5) HCl == (1/5) "\ox*{2,Mn}" Cl2 + (1/2) Cl2 + (1/5) KCl + (4/5) H2O
\end{reaction*}

There are a few possibilities to customize the output.
\begin{beschreibung}
 \option{decimal-marker}{<marker>} the symbol to indicate the decimal. Default =
   \code{.}
 \option{frac-style}{math|xfrac|nicefrac} determines how fractions are displayed.
   Default = \code{math}
 \option{stoich-space}{<skip>} The space that is placed after the stoichiometric
   factor. A rubber length. Default = \code{.1667em plus .0333em minus .0117em}
\end{beschreibung}
\begin{beispiel}
 \ch[decimal-marker={,}]{3.5} \ch[decimal-marker={$\cdot$}]{3,5} 
\end{beispiel}

The option \key{frac-style}{xfrac} uses the \lstinline+\sfrac+ command of the
\paket{xfrac} package. The output strongly depends on the font you use.\secidx[xfrac]{Stoichiometric Factors}
\begin{beispiel}
 \ch[frac-style=xfrac]{3/2} \ch[frac-style=xfrac]{1_1/2}
\end{beispiel}
\chemformula defines the instance \lstinline=formula-text-frac= which you can
redefine to your needs. See the \paket{xfrac} documentation for further information.
The default definition is this:
\begin{beispiel}[code only]
 \DeclareInstance{xfrac}{chemformula-text-frac}{text}
  {
    slash-left-kern  = -.15em ,
    slash-right-kern = -.15em
  }
\end{beispiel}
This document uses the font Linux Libertine and the following definition:
\begin{beispiel}[code only]
 \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
  }
\end{beispiel}

The option \key{frac-style}{nicefrac} uses the \lstinline+\nicefrac+ command of
the \paket{nicefrac} package.\secidx[nicefrac]{Stoichiometric Factors}
\begin{beispiel}
 \ch[frac-style=nicefrac]{3/2} \ch[frac-style=nicefrac]{1_1/2}
\end{beispiel}

The option \key{stoich-space} allows you to customize the space between
stoichiometric factor and the group following after it.\secidx[space]{Stoichiometric Factors}
\begin{beispiel}
 \ch{2 H2O} \\
 \ch[stoich-space=.3em]{2 H2O}
\end{beispiel}
\secidx*{Stoichiometric Factors}

\section{Compounds}\label{ssec:compounds}\secidx{Compounds}
\chemformula determines compounds as the type that ``doesn't fit in anywhere else.''
This point will become more clear when you know what the other types are.
\begin{beispiel}
 \ch{H2SO4} \\
 \ch{[Cu(NH3)4]^2+}
\end{beispiel}

\subsection{Adducts}\secidx[adducts]{Compounds}
\chemformula has two identifiers which will create adducts.
\begin{beschreibung}
 \befehl{ch}{A.B}
 \befehl{ch}{A*B}
\end{beschreibung}
\begin{beispiel}
 \ch{CaSO4.H2O} \\
 \ch{CaSO4*H2O}
\end{beispiel}
Since numbers in a compound always are treated as subscripts (see
section~\ref{ssec:subscripts}) you sometimes need to introduce stoichiometric
factors for the right output:
\begin{beispiel}
 \ch{Na3PO4*12H2O} \\
 \ch{Na3PO4* 12 H2O} \\
 \ch{Na3PO4 * 12 H2O}
\end{beispiel}

\subsection{Subscripts}\label{ssec:subscripts}\secidx[subscripts]{Compounds}
\emph{All} numbers in a compound are treated as subscripts.
\begin{beispiel}
 \ch{H2SO4}
\end{beispiel}
If you want a letter to be a subscript you can use the math syntax:
\begin{beispiel}
 \ch{A_nB_m}
\end{beispiel}
The subscript recognizes groups. You can also use math inside it.
\begin{beispiel}
 \ch{A_{$n$}B_{$m$}} \\
 \ch{NaCl_{(aq)}}
\end{beispiel}

\subsection{Commands}\secidx[commands]{Compounds}
Commands are allowed in a compound:
\begin{beispiel}
 \ch{\textbf{A2}B3} \ch{A2\color{red}B3}
\end{beispiel}
However, if the commands demand numbers as argument, \eg space commands or
\chemmacros' \lstinline+\ox+ command the direct use will fail. This is because
the numbers are treated as subscripts \emph{before} the command expands.
\begin{beispiel}[code only]
 \ch{A\hspace{2mm}B} will raise an error because \hspace sees something like
 this: \hspace{$_2$mm}. Actually not at all like it but equally bad\ldots
\end{beispiel}
See section~\ref{ssec:text} for a way around this.

\subsection{Charges and Other Superscripts}\secidx[charges]{Compounds}\secidx[superscripts]{Compounds}
\paragraph{Basics}
If a compound \emph{ends} with a plus or minus sign it will be treated as charge
sign and typeset as superscript. In other places a plus is treated as a triple
bond and a dash will be used as a single bond, see section~\ref{ssec:bonds}.
\begin{beispiel}
 \ch{A+B} \ch{AB+} \\
 \ch{A-B} \ch{AB-}
\end{beispiel}

For longer charge groups or other superscripts you can use the math syntax. It
recognizes groups and you can use math inside them. Inside these groups neither
\code{+} nor \code{-} are treated as bonds. If a dot \code{.} is inside a
superscript it is treated as indicator for a radical. A \code{*} gives the
excited state.
\begin{beispiel}
 \ch{A^{x-}} \\
 \ch{A^x-} \\
 \ch{A^{x}-} \\
 \ch{A^{$x-$}} \\
 \ch{RNO2^{-.}} \\
 \ch{^31H} \\
 \ch{^{14}6C} \\
 \ch{^{58}_{26}Fe} \\
 \ch{NO^*}
\end{beispiel}

Ions and ion composites with more than one charge can be typeset quite as easy:
\begin{beispiel}
 \ch{SO4^2-} \ch{Ca^2+ SO4^2-}
\end{beispiel}

\paragraph{Charge Commands}\secidx[superscripts!charge commands]{Compounds}
You don't need to use \cmd{mch} and related commands inside \cmd{ch}. Indeed,
you \emph{shouldn't} use them as they might mess with the subscript and superscript
alignment. The \chemmacros option \code{circled} is obeyed by \cmd{ch}.
\begin{beispiel}
 \chemsetup[option]{circled=all}
 \ch{H+ + OH- <=> H2O}
\end{beispiel}

\paragraph{Behaviour}\secidx[superscripts!behaviour]{Compounds}
The supercripts behave differently depending on their position in a compound, if
there are super- and subscripts following each other directly.
\begin{beispiel}
 \ch{^33B} \ch{{}^33B} \ch{3^3B} \ch{B^3} \ch{B3^3} \\
 \ch{^{23}_{123}B} \ch{{}^{23}_{123}B}  \ch{_{123}^{23}B} \ch{B^{23}} \ch{B_{123}^{23}} \\
 \ch{^{123}_{23}B} \ch{{}^{123}_{23}B}  \ch{_{23}^{123}B} \ch{B^{123}} \ch{B23^{123}}
\end{beispiel}
\begin{itemize}
 \item If a compound \emph{starts} with a sub- or superscript both sub- and
 superscript are aligned to the \emph{right} else to the \emph{left}.
 \item If a compound \emph{does not start} with a sub- or superscript and there
 is both a sub- and a superscript, the superscript is shifted additionally by a
 length determined from the option \key{charge-hshift}{<dim>}, also see
 page~\pageref{desc:charge-hshift}f.
\end{itemize}
The second point follows \ac{iupac}'s recommendations:
\begin{zitat}[{\acs{iupac} Green Book {\cite[][p.\,51]{iupac:greenbook}}}]
 In writing the formula for a complex ion, spacing for charge number can be added
 (staggered arrangement), as well as parentheses: \ch[charge-hshift=full]{SO4^2-},
 \ch{(SO4)^2-} The staggered arrangement is now recommended.
\end{zitat}

\subsection{Bonds}\label{ssec:bonds}\secidx[bonds]{Compounds}
\subsubsection{Native Bonds}
There are three kinds of what I will call ``native bonds'':
\begin{beispiel}
 single: \ch{CH3-CH3} \\
 double: \ch{CH2=CH2} \\
 triple: \ch{CH+CH}
\end{beispiel}

\subsubsection{Flexible Bonds}
\paragraph{Predefined Bonds}
In addition to the three native bonds there are a few more which can be called by
\begin{beschreibung}
 \Befehl{bond}{<bond name>}
\end{beschreibung}
The predefined bond types are shown in table~\ref{tab:bond_types}.

\begin{table}
 \centering
 \caption{Bonds available with \protect\cmd{bond}.}
 \label{tab:bond_types}
 \begin{tabular}{lcl}
  \toprule
   \bfseries name & \bfseries appearance & \bfseries aliases \\
  \midrule
   \code{single}  & \bond{single}        & \code{normal}, \code{sb} \\
   \code{double}  & \bond{double}        & \code{db} \\
   \code{triple}  & \bond{triple}        & \code{tp} \\
   \code{dotted}  & \bond{dotted}        & \code{semisingle} \\
   \code{deloc}   & \bond{deloc}         & \code{semidouble} \\
   \code{tdeloc}  & \bond{tdeloc}        & \code{semitriple} \\
   \code{co>}     & \bond{co>}           & \code{coordright} \\
   \code{<co}     & \bond{<co}           & \code{coordleft} \\
  \bottomrule
 \end{tabular}
\end{table}

\begin{beispiel}
 \ch{C\bond{sb}C\bond{db}C\bond{tp}C\bond{deloc}C\bond{tdeloc}C\bond{co>}C\bond{<co}C}
\end{beispiel}

\paragraph{Own Bonds}
\chemformula offers commands to define own bond types:
\begin{beschreibung}
 \Befehl{DeclareChemBond}{<name>}\ma{<code>}
 \Befehl{RenewChemBond}{<name>}\ma{<code>}
 \Befehl{DeclareChemBondAlias}{<new name>}\ma{<old name>}
 \Befehl{ShowChemBond}{<name>}
\end{beschreibung}
The usage is best described with an example. So let's see how the \code{single}
bond and the \code{co>} bond are defined:
\begin{beispiel}[code only]
 \DeclareChemBond{single}
   { \draw[chembond] (chemformula-bond-start) -- (chemformula-bond-end) ; }
 \DeclareChemBond{coordright}
   { \draw[chembond,butt cap->] (chemformula-bond-start) -- (chemformula-bond-end) ; }
 \DeclareChemBondAlias{co>}{coordright}
\end{beispiel}
Two points are important: the names of the starting and the ending coordinates,
\code{chemformula-bond-start} and \code{chemformula-bond-end}, and the \TikZ
style of the bonds \code{chembond}.

So, let's say you want to define a special kind of dashed bond. You could do this:
\begin{beispiel}
 \usetikzlibrary{decorations.pathreplacing}
 \makeatletter
 \DeclareChemBond{dashed}
   {
     \draw[
       chembond,
       decorate,
       decoration={ticks,segment length=\chemformula@bondlength/10,amplitude=1.5pt}]
       (chemformula-bond-start) -- (chemformula-bond-end) ;
   }
 \makeatother
 \chemsetup[chemformula]{bond-length=2ex}
 \ch{C\bond{dashed}C}
\end{beispiel}

The last example showed you another macro: \makeatletter\cmd{chemformula@bondlength}\makeatother.
It only exists so you can use it to access the bond length as set with \key{bond-length}
directly.% (see also page~\pageref{key:bond-length}).

\subsection{Customization}\secidx[customization]{Compounds}\label{ssec:compounds:customization}
These options allow you to customize the ouptut of the compounds:
\begin{beschreibung}
 \option{subscript-vshift}{<dim>} Extra vertical shift of the subscripts. Default
   = \code{0pt}
 \option{subscript-style}{text|math} Style that is used to typeset the subscripts.
   Default = \code{text}
 \option{charge-hshift}{<dim>} Shift of superscripts when following a subscript.
   Default = \code{.25em}\label{desc:charge-hshift}
 \option{charge-vshift}{<dim>} Extra vertical shift of the superscripts.
   Default = \code{0pt}
 \option{charge-style}{text|math} Style that is used to typeset the superscripts.
   Default = \code{text}
 \option{adduct-space}{<dim>} Space to the left and the right of the adduct point.
   Default = \code{.1333em}
 \option{bond-length}{<dim>} The length of the bonds. Default = \code{.5833em}
 \option{bond-offset}{<dim>} Space between bond and atoms. Default = \code{.07em}
 \option{bond-style}{<tikz>} \TikZ\ options for the bonds. Initially empty.
 \option{radical-style}{<tikz>} \TikZ\ options for the radical point. Initially
   empty.
 \option{radical-radius}{<dim>} The radius of the radical point. Default =
   \code{.2ex}
\end{beschreibung}

Maybe you have noticed that charges of certain ions are shifted to the right.\secidx[charges!shift]{Compounds}
\begin{beispiel}
 \ch{SO4^2-} \ch{NH4+} \ch{Na+}
\end{beispiel}
They are shifted if they \emph{follow} a subscript which follows \ac{iupac}
recommendations~\cite[][p.\,51]{iupac:greenbook}. The amount of the shift can be
set with the option \key{charge-hshift}.
\begin{beispiel}
 \ch{SO4^2-} \ch{NH4+} \ch{Na+} \\
 \chemsetup[chemformula]{charge-hshift=.5ex}
 \ch{SO4^2-} \ch{NH4+} \ch{Na+} \\
 \chemsetup[chemformula]{charge-hshift=.5pt}
 \ch{SO4^2-} \ch{NH4+} \ch{Na+}
\end{beispiel}

Despite \ac{iupac}'s recommendation \chemformula does not make fully staggered
arrangements in the default setting as I find it hard to read in some cases and
ugly in others. Since this is a subjective decision \chemformula not only let's
you define the absolute amount of the shift but also provides a possibility for
full staggered arrangements. For this you have to use \key{charge-hshift}{full}.
\begin{beispiel}
 \ch[charge-hshift=0pt]{C5H11+} \ch[charge-hshift=0pt]{SO4^2-} \\
 \ch{C5H11+} \ch{SO4^2-} \\
 \ch[charge-hshift=1ex]{C5H11+} \ch[charge-hshift=1ex]{SO4^2-} \\
 \ch[charge-hshift=full]{C5H11+} \ch[charge-hshift=full]{SO4^2-}
\end{beispiel}

If you don't want the charges to be typeset in text mode you can switch to math
mode:
\begin{beispiel}
 \ch{M^x+} \ch{SO4^2-} \\
 \chemsetup[chemformula]{charge-style = math}
 \ch{M^x+} \ch{SO4^2-}
\end{beispiel}

The option \key{subscript-vshift} can be used to adjust the vertical shift of
the subscripts:\secidx[subscripts!shift]{Compounds}
\begin{beispiel}
 \ch{H2SO4} \ch{Na3PO4} \\
 \chemsetup[chemformula]{subscript-vshift=.5ex}
 \ch{H2SO4} \ch{Na3PO4} \\
 \chemsetup[chemformula]{subscript-vshift=-.2ex}
 \ch{H2SO4} \ch{Na3PO4}
\end{beispiel}

You can choose the mode subscripts are typeset in the same way as it is possible
for the charges:
\begin{beispiel}
 \ch{A_nB_m} \ch{H2SO4} \\
 \chemsetup[chemformula]{subscript-style = math}
 \ch{A_nB_m} \ch{H2SO4}
\end{beispiel}

The option \key{adduct-space} sets the space left and right to the adduct symbol
$\cdot$.
\begin{beispiel}
 \ch{Na3PO3*H2O} \\
 \chemsetup[chemformula]{adduct-space=.2em}
 \ch{Na3PO3*H2O}
\end{beispiel}

Changing the length of the bonds:\secidx[bonds!length]{Compounds}
\begin{beispiel}
 \chemsetup[chemformula]{bond-length=4mm}%
 single: \ch{CH3-CH3} \\
 double: \ch{CH2=CH2} \\
 triple: \ch{CH+CH}
\end{beispiel}

You can change the distance between bond and atom, too:
\begin{beispiel}
 \ch{H-H + N+N + O=O} \\
 \ch[bond-offset=1pt]{H-H + N+N + O=O}
\end{beispiel}
\secidx*{Compounds}

\section{Special Input Types}\secidx{Special Types}
There are some \enquote{special type} input groups.

\subsection{Single Token Groups}\secidx[single token groups]{Special Types}
The first kind are groups which consist of only one token, namely of the
following ones:
\begin{beschreibung}
 \befehl{ch}{ + } \ch{+} creates the plus sign between compounds with space
   around it:\\
   \cmd{ch}{2 Na + Cl2} \ch{2 Na + Cl2}
 \befehl{ch}{ v } \ch{v} sign for precipitate: \cmd{ch}{BaSO4 v} \ch{BaSO4 v}
 \befehl{ch}{ \lstinline+^+ } \ch{^} sign for escaping gas\footnotemark:
   \cmd{ch}{\lstinline=H2 ^=} \ch{H2 ^}
\end{beschreibung}
\footnotetext{Is this the correct English term? Please correct me if it isn't.}

The space left and right of the plus sign can be set with this option:
\begin{beschreibung}
 \option{plus-space}{<skip>} A rubber length. Default = \code{.3em plus .1em minus .1em}
\end{beschreibung}
\begin{beispiel}
 \ch{A + B}\\
 \ch[plus-space=4pt]{A + B}
\end{beispiel}

\subsection{Option Input}\secidx[option input]{Special Types}
\achtung{This is an experimental feature and may well be dropped in future versions.}
Sometimes you might want to apply an option only to a part of a, say, reaction.
Of course you have the possibility to use \cmd{ch} several times.
\begin{beispiel}
 \ch{H2O +}\textcolor{red}{\ch{H2SO4}}\ch{-> H3O+ + HSO4-} \\
 \ch{H2O +}\ch[subscript-vshift=2pt]{H2SO4}\ch{-> H3O+ + HSO4-}
\end{beispiel}
This, however, interrupts the input in your source and \emph{may} mess with the
spacing. That's why there is an alternative:
\begin{beschreibung}\makeatletter
 \befehl{ch}{ @\{<options>\} } The options specified this way will be valid
   \emph{only} until the next compound is set.
\end{beschreibung}
\begin{beispiel}
 \ch{H2O +}\textcolor{red}{\ch{H2SO4}}\ch{-> H3O+ + HSO4-} \\
 \ch{H2O + @{format=\color{red}} H2SO4 -> H3O+ + HSO4-} \\
 or of course:\\
 \ch{H2O + \textcolor{red}{H2SO4} -> H3O+ + HSO4-}\\[1em]
 \ch{H2O +}\ch[subscript-vshift=2pt]{H2SO4}\ch{-> H3O+ + HSO4-} \\
 \ch{H2O + @{subscript-vshift=2pt} H2SO4 -> H3O+ + HSO4-}
\end{beispiel}
\secidx*{Special Types}

\section{Escaped Input}\secidx{Escaped Input}
In some cases it may be desirable to prevent \chemformula from parsing the input.
This can be done in two ways.
\subsection{Text}\label{ssec:text}\secidx[text]{Escaped Input}
If you put something between \lstinline+" "+ or \lstinline+' '+ then the input
will be treated as normal text, except that spaces are not allowed and have to be
input with \lstinline+~+.
\begin{beschreibung}
 \Befehl{ch}{ "<escaped text>" }
 \Befehl{ch}{ '<escaped text>' }
\end{beschreibung}
\begin{beispiel}
 \ch{"\ox{2,Ca}" O} \\
 \ch{"\ldots\," Na + "\ldots\," Cl2 -> "\ldots\," NaCl} \\
 \ch{'A~->~B'}
\end{beispiel}
In many cases you won't need to escape the input. But when you get into trouble
when using a command inside \cmd{ch} try hiding it.

\subsection{Math}\secidx[math]{Escaped Input}
If you especially want to input math you just enclose it with \lstinline+$ $+.
This output is different from the escaped text as it is followed by a space.
\begin{beschreibung}\catcode`\$=11
 \Befehl{ch}{ $<escaped math>$ }
\end{beschreibung}
\begin{beispiel}
 escaped text: \ch{"$x$" H2O} \\
 escaped math: \ch{$x$ H2O} \\
 \ch{$2n$ Na + $n$ Cl2 -> $2n$ NaCl}
\end{beispiel}

The space that is inserted after a math group can be edited:
\begin{beschreibung}
 \option{math-space}{<skip>} A rubber length. Default =
   \code{.1667em plus .0333em minus .0117em}
\end{beschreibung}
\begin{beispiel}
 \ch{$2n$ Na + $n$ Cl2 -> $2n$ NaCl} \\
 \chemsetup[chemformula]{math-space=.25em}
 \ch{$2n$ Na + $n$ Cl2 -> $2n$ NaCl} \\
 \ch{$A->B$}
\end{beispiel}
\secidx*{Escaped Input}

\section{Arrows}\label{sec:arrows}\secidx{Arrows}
\subsection{Arrow types}\secidx[types]{Arrows}
Arrows are input in the same intuitive way they are with \paket{mhchem}. There
are various different types:
\begin{beschreibung}
 \befehl{ch}{ -> } \ch{->} standard right arrow
 \befehl{ch}{ <- } \ch{<-} standard left arrow
 \befehl{ch}{ -/> } \ch{-/>} does not react (right)
 \befehl{ch}{ </- } \ch{</-} does not react (left)
 \befehl{ch}{ <-> } \ch{<->} resonance arrow
 \befehl{ch}{ <> } \ch{<>} reaction in both directions
 \befehl{ch}{ == } \ch{==} stoichiometric equation
 \befehl{ch}{ <=> } \ch{<=>} equilibrium arrow
 \befehl{ch}{ \lstinline+<=>>+ } \ch{<=>>} unbalanced equilibrium arrow to the right
 \befehl{ch}{ \lstinline+<<=>+ } \ch{<<=>} unbalanced equilibrium arrow to the left
 \befehl{ch}{ <o> } \ch{<o>} isolobal arrow
\end{beschreibung}
All these arrows are drawn with \TikZ.
\begin{beispiel}
 \ch{H2 + Cl2 -> 2 HCl} \\
 \ch{H2O + CO3^2- <=> OH- + HCO3-} \\
 \ch{A <- B} \\
 \ch{\{[CH2=CH-CH2]- <-> [CH2-CH=CH2]- \}} \\
 \ch{A <> B} \\
 \ch{H+ + OH- <=>> H2O} \\
 \ch{2 NO2 <<=> N2O4}
\end{beispiel}

\subsection{Labels}\secidx[labels]{Arrows}
The arrows take two optional arguments to label them.
\begin{beschreibung}
 \Befehl{ch}{ ->[<above>][<below>] }
\end{beschreibung}
\begin{beispiel}
 \ch{A ->[a] B} \\
 \ch{A ->[a][b] B} \\
 \ch{A ->[\SI{100}{\celsius}] B}
\end{beispiel}
The label text can be parsed seperately from the arrow. The recipe is easy: leave
blanks.
\begin{beispiel}
 \ch{A ->[H2O] B} \\
 \ch{A ->[ H2O ] B} \\
 \ch{A ->[ "\ox{2,Ca}" F2 ] B} \\
 \ch{A ->[$\Delta$,~ \[H+ \]] B}
\end{beispiel}
If you leave the blanks \chemformula treats the groups inside the square brackets
as seperated input types. The arrow reads its arguments \emph{afterwards}. As you
can see the arrows \enquote{grow} with the length of the labels. What stays
constant is the part that protrudes the labels. As you also can see in the last
example square brackets inside the arrow arguments should be produced using \cmd{[}
and \cmd{]}. They keep their usual meaning outside \cmd{ch}. These commands are
necessary since the usual grouping (\ie hiding the brackets inside curly brackets)
doesn't work due to the way \cmd{ch} reads its argument.
\begin{beispiel}
 \ch{A ->[a] B} \\
 \ch{A ->[ab] B} \\
 \ch{A ->[abc] B} \\
 \ch{A ->[abc~abc] B} \\
 % needs the `chemfig' package:
 \setatomsep{15pt}
 \ch{A ->[ "\chemfig{-[:30]-[:-30]OH}" ] B} \\
 \ch{A ->[[]] B} vs. \ch{A ->[\[\]] B}
\end{beispiel}

\subsection{Customization}\secidx[customization]{Arrows}
These are the options which enable you to customize the arrows:
\begin{beschreibung}
 \option{arrow-offset}{<dim>} This is the length that an arrow protrudes a label
   on both sides. This means an empty arrow's length is two times \code{arrow-offset}.
   Default = \code{.75em}
 \option{arrow-yshift}{<dim>} Shifts an arrow up (positive value) or down (negative
   value). Default = \code{0pt}
 \option{arrow-ratio}{<factor>} The ratio of the arrow lengths of the unbalanced
   equilibrium. \code{.4} would mean that the length of the shorter arrow is
   $0.4\times$ the length of the longer arrow. Default = \code{.6}
 \option{compound-sep}{<dim>} The space between compounds and the arrows.
   Default = \code{.5em}
 \option{label-offset}{<dim>} The space between the labels and the arrows.
   Default = \code{2pt}
 \option{label-style}{<font command>} The relative font size of the labels.
   Default = \lstinline+\footnotesize+
\end{beschreibung}

The following code shows the effect of the different options on the \lstinline+<=>>+
arrow:
\begin{beispiel}
 standard: \ch{A <=>>[x][y] B} \\
 longer: \ch[arrow-offset=12pt]{A <=>>[x][y] B} \\
 higher: \ch[arrow-yshift=2pt]{A <=>>[x][y] B} \\
 more balanced: \ch[arrow-ratio=.8]{A <=>>[x][y] B} \\
 labels further away: \ch[label-offset=4pt]{A <=>>[x][y] B} \\
 larger distance to compounds: \ch[compound-sep=2ex]{A <=>>[x][y] B} \\
 smaller labels: \ch[label-style=\tiny]{A <=>[x][y] B}
\end{beispiel}

\subsection{Modify Arrow Types}\label{sec:arrows_modify}\secidx[types!modify]{Arrows}
The arrows are defined with the command
\begin{beschreibung}
 \Befehl{DeclareChemArrow}{<tokens>}\ma{<tikz>}
\end{beschreibung}
\ma{<tokens>} is the sequence of tokens that is replaced with the actual arrow code.
For example the basic arrow is defined via
\begin{beispiel}[code only]
 \DeclareChemArrow{->}{\draw[-cf] (cf_arrow_start) -- (cf_arrow_end) ;}
\end{beispiel}
In order to define arrows yourself you need to know the basics of \TikZ\footnote{Please
see the \textsf{pgfmanual} for details.}. There are some predefined coordinates
you can and should use:
\begin{description}
 \item[\code{(cf\_arrow\_start)}] The beginning of the arrow.
 \item[\code{(cf\_arrow\_end)}] The end of the arrow.
 \item[\code{(cf\_arrow\_mid)}] The mid of the arrow.
 \item[\code{(cf\_arrow\_mid\_start)}] The beginning of the shorter arrow in
   types like \lstinline+<=>>+.
 \item[\code{(cf\_arrow\_mid\_end)}] The end of the shorter arrow in types like
   \lstinline+<=>>+.
 \item[\code{cf}, \code{left cf}, \code{right cf}] \chemformula's own arrow heads.
\end{description}
\begin{beispiel}
 \DeclareChemArrow{.>}{\draw[-cf,dotted,red] (cf_arrow_start) -- (cf_arrow_end);}
 \DeclareChemArrow{n>}{\draw[-cf] (cf_arrow_start) .. controls ([yshift=3ex]cf_arrow_mid) .. (cf_arrow_end);}
 \ch{A .> B} \ch{A .>[a][b] B} \ch{A n> B}
\end{beispiel}
If you want to redefine an existing arrow there are two commands you can use:
\begin{beschreibung}
 \Befehl{RenewChemArrow}{<tokens>}\ma{<tikz>}
 \Befehl{ShowChemArrow}{<tokens>}
\end{beschreibung}
The second one gives the current definition, the first one redefines an existing
arrow.
\begin{beispiel}
 \texttt{\ShowChemArrow{->}} \\
 \RenewChemArrow{->}{\draw[->,red] (cf_arrow_start) -- (cf_arrow_end) ;}
 \texttt{\ShowChemArrow{->}} \\
 \ch{A -> B}
\end{beispiel}
\secidx*{Arrows}

\section{Names}\secidx{Names}
\subsection{Syntax}\secidx[syntax]{Names}
\chemformula has a built-in syntax to write text under a compound. In a way it
works very similar to the arrows.
\begin{beschreibung}
 \Befehl{ch}{ !(<name>)( <formula> ) }
\end{beschreibung}
If an exclamation mark is followed by a pair of parentheses \chemformula will
parse it this way:
\begin{beispiel}
 \ch{!(ethanol)( CH2CH2OH )}
\end{beispiel}
The same what's true for the arrows arguments holds for these arguments: if you
leave blanks the different parts will be treated according to their input type
before the text is set below the formula.
\begin{beispiel}
 \ch{!(water)(H2O)} \quad
 \ch{!( "\textcolor{blue}{water}" )( H2O )} \quad
 \ch{!( $2n-1$ )( H2O )} \quad
 \ch{!( H2O )( H2O )} \quad
 \ch{!(oxonium)( H3O+ )}
\end{beispiel}
If for some reason you want to insert an exclamation mark \emph{without} it
creating a name you only have to make sure it isn't followed by parentheses.
\begin{beispiel}
 \ch{H2O~(!)} \\
 \ch{A!{}()}
\end{beispiel}

\subsection{Customization}\secidx[customization]{Names}
\chemformula provides two options to customize the output of the names:
\begin{beschreibung}
 \option{name-format}{<commands>} The format of the name. This can be arbitrary
   input. Default = \lstinline+\scriptsize\centering+
 \option{name-width}{<dim>|auto} The width of the box where the label is put into.
   \code{auto} will detect the width of the name and set the box to this width.
   Default = \code{auto}
\end{beschreibung}
\begin{beispiel}
 \ch{!(acid)( H2SO4 ) -> B} \\
 \ch[name-format=\sffamily\small]{!(acid)( H2SO4 ) -> B} \\
 \ch[name-format=\scriptsize N:~]{!(acid)( H2SO4 ) -> B} \\
 \ch[name-width=3em,name-format=\scriptsize\raggedright]{!(acid)( H2SO4 ) -> B}
\end{beispiel}
\secidx*{Names}

\section{Format and Font}\secidx{Format and Font}\label{sec:format}
In the standard setting \chemformula doesn't make any default changes to the font
of the formula output. Let's take a look at a nonsense input which shows all features:
\begin{beispiel}
 \newcommand*\sample{\ch{H2C-C+C-CH=CH+ + CrO4^2- <=>[x][y] 2.5 Cl^{-.} + 3_1/2 Na*OH_{(aq)} + !(name)( A^n ) "\LaTeXe"}}
 \sample
\end{beispiel}
\newcommand*\sample{\ch{H2C-C+C-CH=CH+ + CrO4^2- <=>[x][y] 2.5 Cl^{-.} + 3_1/2 Na*OH_{(aq)} + !(name)( A^n ) "\LaTeXe"}}
Now we're going to change different aspects of the font a look what happens:
\begin{beispiel}[below]
 \sffamily Hallo \sample \\
 \ttfamily Hallo \sample \normalfont \\
 \bfseries Hallo \sample \normalfont \\
 \itshape Hallo \sample
\end{beispiel}
As you can see most features adapt to the surrounding font.

If you want to change the default format you need to use this option:
\begin{beschreibung}
 \option{format}{<anything>} Adds arbitrary code before the output of \cmd{ch}.
\end{beschreibung}
\begin{beispiel}
 \definecolor{newblue}{rgb}{.1,.1,.5}\chemsetup[chemformula]{format=\color{newblue}\sffamily}
 \sffamily Hallo \sample \\
 \ttfamily Hallo \sample \normalfont \\
 \bfseries Hallo \sample \normalfont \\
 \itshape Hallo \sample
\end{beispiel}

You can also specifically change the fontfamily, fontseries and fontshape of the output.
\begin{beschreibung}
 \option{font-family}{<family>} Changes the fontfamily of the output with
   \lstinline+\fontfamily{<family>}\selectfont+.
 \option{font-series}{<series>} Changes the fontseries of the output with
   \lstinline+\fontseries{<series>}\selectfont+.
 \option{font-shape}{<shape>} Changes the fontshape of the output with
   \lstinline+\fontshape{<shape>}\selectfont+.
\end{beschreibung}
\begin{beispiel}
 \chemsetup[chemformula]{font-series=bx}
 Hallo \sample \\
 \sffamily Hallo \sample \normalfont \\
 \chemsetup[chemformula]{font-family=lmr,font-series=m} Hallo \sample \normalfont \\
 \itshape Hallo \sample
\end{beispiel}

If you're using \hologo{XeLaTeX} or \hologo{LuaLaTeX} and have loaded \paket{fontspec}
you have the possibilty to set the font with it:
\begin{beschreibung}
 \Option{font-spec}{\{<font>\}} or with options
 \Option{font-spec}{\{[<options>]<font>\}}
\end{beschreibung}
\begin{beispiel}
 \chemsetup[chemformula]{font-spec={Linux Biolinum O}} \sample \\
 \chemsetup[chemformula]{font-spec={[Color=darkgray]Augie}} \sample \\
 \chemsetup[chemformula]{font-spec={Tipbrush Script}} \sample \\
 \chemsetup[chemformula]{font-spec={Latin Modern Sans}} \sample \\
 \bfseries \sample \normalfont \\
 \chemsetup[chemformula]{font-spec={Feathergraphy Decoration}} \sample
\end{beispiel}
\secidx*{Format and Font}

\section{Usage In Math Equations}\secidx{Math Environments}
The \cmd{ch} command can be used inside math equations. It recognizes
\lstinline+\\+ and \lstinline+&+ and passes them on. However, you can't use the
optional arguments of \lstinline+\\+ inside \cmd{ch}.
\begin{beispiel}
 \begin{align}
  \ch{
    H2O & ->[a] H2SO4 \\
    Cl2 & ->[x][y] CH4
  }
 \end{align}
 \begin{align*}
 \ch{
   RNO2      &<=>[ + e- ] RNO2^{-.} \\
   RNO2^{-.} &<=>[ + e- ] RNO2^2-
 }
 \end{align*}
\end{beispiel}
\secidx*{Math Environments}

\section{Further Examples}
This section presents some examples of a possible usage.

\begin{beispiel}
 \begin{reaction}[Synthese von Alkanen]
  !(Synthesegas)( $n$ CO + $(2n+1)$ H2 ) ->[\SI{200}{\celsius}][\[CoNi\]] C_{$n$}H_{$2n+2$} + $n$ H2O
 \end{reaction}
\end{beispiel}

\begin{beispiel}
 \begin{reactions*}
  "a)" && CH4    + Cl2 &-> CH3Cl  + HCl && "{\small Chlormethan/Methylchlorid}" \\
  "b)" && CH3Cl  + Cl2 &-> CH2Cl2 + HCl && "{\small Dichlormethan/Methylenchlorid}" \\
  "c)" && CH2Cl2 + Cl2 &-> CHCl3  + HCl && "{\small Trichlormethan/Chloroform}" \\
  "d)" && CHCl3  + Cl2 &-> CCl4   + HCl && "{\small Tetrachlormethan/Tetrachlorkohlenstoff}"
 \end{reactions*}
\end{beispiel}

\begin{beispiel}
 \chemsetup[ox]{parse=false}\ch{"\ox{\delm,C}" -{} "\ox{\delp,M}" \qquad ( <-> "\ox{\delp,C}" -{} "\ox{\delm,Br}" )} \\
 \ch[adduct-space=0pt]{X. + .Y <=> X-Y + Bindungsenergie} \\
 \ch[name-format=\normalsize]{!(\State{H}{f}\qquad)() !(\textcolor{red}{??})( CH4\gas{} ) + !(\num{0})( 2 O2\gas{} ) -> !(\num{-94.3})( CO2\gas{} ) + !(\num{-57.9})( H2O\lqd{} ) + !(\num{-192.1})( "\State{H}" )}
\end{beispiel}

\begin{beispiel}
 \begin{reactions*}
  CH3MgBr + "\ox*{1,Cu}" X &-> "\glqq" CH3 "\ox*{1,Cu}\grqq" + MgBrX "\qquad X~$=$~Br,I,CN" \\
  2 MeLi + CuI             &-> !(Dimethylcuprat~(Gilmann-Cuprat))( Me2CuLi ) + Li
 \end{reactions*}
\end{beispiel}

\begin{beispiel}
 % needs `chemfig'
 \begin{reactions*}
  H3C-CH3 + Cl2                           &->[$\Delta$][$h\nu$] H3CCH2Cl + HCl       & &"\Enthalpy{-27.1}" \\
  H3C-CH3 + "\Lewis{0.,Cl}"               &-> H3CCH2 "\Lewis{0.,\vphantom{H}}" + HCl & &"\Enthalpy{-5.0}" \\
  H3C-CH2 "\Lewis{0.,\vphantom{H}}" + Cl2 &-> H3CCH2Cl + "\Lewis{0.,Cl}"             & &"\Enthalpy{-23.0}"
 \end{reactions*}
\end{beispiel}

The following example shows how the cancelling of compounds could be done%
\footnote{Inspired by a question on TeX.SE: \url{http://tex.stackexchange.com/q/30118/5049}}.
\begin{beispiel}
 % needs `cancel'
 \begin{align*}
  \ch{\cancel{HCOOH\aq} + H2O\lqd{}  &<=> H3O^+\aq{} + \cancel{HCOO^-\aq}} \\
  \ch{\cancel{HCOO^-\aq} + H2O\lqd{} &<=> \cancel{HCOOH\aq} + OH^-\aq}\\[-1ex]
  \cline{1-2}
  \ch{H2O\lqd{} + H2O\lqd{} &<=> H3O^+\aq{} + OH^-\aq}    
 \end{align*}
\end{beispiel}
\secidx*{CHEMFORMULA}

\part{\texorpdfstring{\Ghsystem}{ghsystem}}\secidx{GHSYSTEM}\label{part:ghsystem}
\section{Setup}
All of \ghsystem's options belong to the module \textcolor{module}{\code{ghsystem}}.
This means they can be setup with
\begin{beispiel}[code only]
 \chemsetup[ghsystem]{<options>} or
 \chemsetup{ghsystem/<option1>,ghsystem/<option2>}
\end{beispiel}

\section{Get Hazard and Precautionary Statements}\secidx{Hazard and Precautionary Statements}
\subsection{Simple Statements}\secidx[get statements]{GHSYSTEM}
The general usage is simple: you use the command
\begin{beschreibung}
 \Befehl{ghs}*[<options>]{<type>}\ma{<number>}
\end{beschreibung}
There are three types available: \code{h}, \code{euh} and \code{p}. The \ma{<type>}
argument is case insensitive, so just type them in as you like.
\begin{beispiel}
 \ghs{h}{200} \\
 \ghs{H}{224} \\
 \ghs{euh}{001} \\
 \ghs{Euh}{202} \\
 \ghs{p}{201}
\end{beispiel}

The starred version hides the identifier and only gives the statement. If you want
to hide the statement itself instead you can use the option:
\begin{beschreibung}
 \Option{hide}{\default{true}|false}
\end{beschreibung}

There is an option to customize the output, too.
\begin{beschreibung}
 \option{space}{<space command>} Space between \code{<type>} and \code{<number>}.
\end{beschreibung}
\begin{beispiel}
 \ghs{h}{200} \\
 \ghs[space=\,]{h}{200} \\
 \ghs*{h}{200} \\
 \ghs[hide]{h}{200}
\end{beispiel}

\subsection{Statements with Placeholders}\secidx[statements with placeholders]{GHSYSTEM}
Some of the statements contain placeholders. They can be one of the following:
\begin{itemize}
 \item \textit{\textless state route of exposure if it is conclusively proven that
 no other routes of exposure cause the hazard\textgreater}
 \item \textit{\textless state specific effect if known\textgreater}
 \item \textit{\textless or state all organs affected, if known\textgreater}
 \item \textit{\textless name of sensitising substance\textgreater}
\end{itemize}

Except the last one which needs to be filled in, they are hidden per default. They
can be made visible with the option
\begin{beschreibung}
 \option{fill-in}{\default{true}|false} Show placeholders. Default = \code{false}
\end{beschreibung}
\begin{beispiel}[below]
 \ghs{h}{340} \\
 \ghs[fill-in]{h}{340} \\
 \ghs{h}{360} \\
 \ghs[fill-in]{h}{360} \\
 \ghs{h}{370} \\
 \ghs[fill-in]{h}{370} \\
 \ghs{euh}{208} \\
 \ghs[fill-in]{euh}{208}
\end{beispiel}

These placeholders can be replaced with one of these options:
\begin{beschreibung}
 \option{exposure}{<text>} exposure placeholder
 \option{effect}{<text>} effect placeholder
 \option{organs}{<text>} organ placeholder
 \option{substance}{<text>} substance placeholder
\end{beschreibung}
\begin{beispiel}
 \ghs[exposure=This is how you get exposed.]{h}{340} \\
 \ghs[effect=These are the effects.]{h}{360} \\
 \ghs[organs=to this organ]{h}{370} \\
 \ghs[substance=substance]{euh}{208}
\end{beispiel}

\subsection{Statements with Gaps}\secidx[statements with gaps]{GHSYSTEM}
Some of the statements have gaps that can be filled.
\begin{beispiel}
 \ghs{p}{301} \\
 \ghs{p}{401} \\
 \ghs{p}{411} \\
 \ghs{p}{413}
\end{beispiel}

These gaps can be filled using these options:
\begin{beschreibung}
 \Option{text}{<text>}
 \Option{dots}{<text>}
 \Option{C-temperature}{<num>}
 \Option{F-temperature}{<num>}
 \Option{kg-mass}{<num>}
 \Option{lbs-mass}{<num>}
\end{beschreibung}
\begin{beispiel}
 \ghs[text=contact physician!]{p}{301} \\
 \ghs[dots=here]{p}{401} \\
 \ghs[C-temperature=50, F-temperature=122]{p}{411} \\
 \ghs[kg-mass=5.0, lbs-mass=11, C-temperature=50, F-temperature=122]{p}{413}
\end{beispiel}

\subsection{Combined Statements}\secidx[combined statements]{GHSYSTEM}
There are some combinations of statements. They are input with a \code{+} between
the numbers:
\begin{beispiel}[below]
 \ghs{p}{235+410} \\
 \ghs{p}{301+330+331}
\end{beispiel}

Note that you can only get combinations that officially exist. \emph{You can't
combine freely}.
\secidx*{Hazard and Precautionary Statements}

\section{Pictograms}\secidx{Pictograms}
\subsection{The Pictures}
The \ac{ghs} defines a number of pictograms:

\ghspic{explos} \ghspic{flame} \ghspic{flame-O} \ghspic{bottle} \ghspic{acid}
\ghspic{skull} \ghspic{exclam} \ghspic{health} \ghspic{aqpol}

The command
\begin{beschreibung}
 \Befehl{ghspic}[<options>]{<name>}
\end{beschreibung}
loads them. Table~\ref{tab:ghs_pictograms} shows all available pictograms and their
names. To be more precise: it shows the names to use with the \cmd{ghspic} command.
The file names are \lstinline=ghsystem_<name>.<filetype>= where \code{<filetype>}
is \code{eps}, \code{pdf}, \code{jpg} or \code{png}, see also section~\ref{ssec:picture_type}.
\begin{beispiel}
 \ghspic{skull}
\end{beispiel}

If you don't like the default size you can change it using this option:
\begin{beschreibung}
 \option{scale}{<factor>} Scales the pictogram. Default = \code{1}
\end{beschreibung}
The pictures are actually quite large. The default setting scales them by a factor
of $\frac{1}{20}$.
\begin{beispiel}
 \ghspic[scale=2]{skull}
\end{beispiel}

If you want to use some specific \lstinline=\includegraphics= options, \eg if you
want to rotate the pictogram for some reason, use this option:
\begin{beschreibung}
 \Option{includegraphics}{\{<includegraphics keyvals>\}}
\end{beschreibung}
\begin{beispiel}
 \ghspic[includegraphics={angle=90}]{skull}
\end{beispiel}

\begin{longtable}{>{\ttfamily}ll>{\ttfamily}ll}
    \caption{All available \ac{ghs} pictograms.\label{tab:ghs_pictograms}} \\
  \toprule
    \normalfont\bfseries name & \bfseries pictogram & \normalfont\bfseries name & \bfseries pictogram \\
  \midrule\endfirsthead
  \toprule
    \normalfont\bfseries name & \bfseries pictogram & \normalfont\bfseries name & \bfseries pictogram \\
  \midrule\endhead
  \bottomrule\endfoot
  explos              & \ghspic{explos}          & explos-1            & \ghspic{explos-1} \\
  explos-2            & \ghspic{explos-2}        & explos-3            & \ghspic{explos-3} \\
  explos-4            & \ghspic{explos-4}        & explos-5            & \ghspic{explos-5} \\
  explos-6            & \ghspic{explos-6}        & & \\
  flame               & \ghspic{flame}           & flame-2-white       & \ghspic{flame-2-white} \\
  flame-2-black       & \ghspic{flame-2-black}   & flame-3-white       & \ghspic{flame-3-white} \\
  flame-3-black       & \ghspic{flame-3-black}   & flame-4-1           & \ghspic{flame-4-1} \\
  flame-4-2           & \ghspic{flame-4-2}       & flame-4-3-white     & \ghspic{flame-4-3-white} \\
  flame-4-3-black     & \ghspic{flame-4-3-black} & flame-5-2-white     & \ghspic{flame-5-2-white} \\
  flame-5-2-black     & \ghspic{flame-5-2-black} & & \\
  flame-O             & \ghspic{flame-O}         & flame-O-5-1         & \ghspic{flame-O-5-1} \\
  bottle              & \ghspic{bottle}          & bottle-2-black      & \ghspic{bottle-2-white} \\
  bottle-2-white      & \ghspic{bottle-2-black}  & & \\
  acid                & \ghspic{acid}            & acid-8              & \ghspic{acid-8} \\
  skull               & \ghspic{skull}           & skull-2             & \ghspic{skull-2} \\
  skull-6             & \ghspic{skull-6}         & & \\
  exclam              & \ghspic{exclam}          & & \\
  health              & \ghspic{health}          & & \\
  aqpol               & \ghspic{aqpol}           & & \\
\end{longtable}

\subsection{Picture Type Depending on Engine}\label{ssec:picture_type}
As you probably know you can't use every picture type with every compiler engine.
\pdfTeX{} in \acs{dvi} mode \emph{needs} \code{eps} pictures while
\pdfTeX{} in \acs{pdf} mode, \XeTeX{} and \LuaTeX{} convert
\code{eps} pictures into \code{pdf} files, given they have the rights to write in
the directory the pictures are saved in.

However, the latter can include \code{jpg} and \code{png} without any problems,
while \pdfTeX{} in \acs{dvi} mode can't.

To resolve this \ghsystem tests which engine is used and if \pdfTeX{} which
mode is used and then chooses either \code{eps} or \code{pdf} for the pictograms.
You are free to choose the picture type yourself with the option
\begin{beschreibung}
 \Option{pic-type}{eps|pdf|jpg|png}
\end{beschreibung}
\secidx*{Pictograms}

\section{Available Languages}\label{sec:ghsystem_language}
Right now the H and P statements are only available in English, German or Italian.
The package adapts the package option \key[option]{german} but does not (yet)
recognize language settings by \paket{babel} or \paket{polyglossia}.

You can also choose the language explicitly.
\begin{beschreibung}
 \Option{language}{english|german|italian}
\end{beschreibung}
\begin{beispiel}
 \ghs{h}{201}

 \chemsetup[ghsystem]{language=german}
 \ghs{h}{201}
\end{beispiel}

I will add other languages some time in future. This may take a while, though.
If you would be willing to contribute and write the statements of another language
please feel free to contact me\footnote{\href{mailto:contac@mychemistry.eu}{contact@mychemistry.eu}}.
I would provide you with a template file, a \acs{pdf} containing the official
translations, and help to all your questions.

\section{List of All Statements}\secidx{List of All Statements}
If for some reason you want to list all sentences you can use
\begin{beschreibung}
 \Befehl{ghslistall}[<options>]
\end{beschreibung}

This command has a number of options to customize the table, which is created with
the \lstinline=longtable= environment of the \paket{longtable} package.
\begin{beschreibung}
 \option{table-head-number}{<text>} Default = \code{Identifier}
 \option{table-head-text}{<text>} Default = \code{Statement}
 \option{table-next-page}{<text>} Default = \code{continues on next page}
 \option{table-caption}{<text>} As \code{<text>} in \lstinline=\caption{<text>}=.
   Default = \code{All H, EUH, and P Statements.}
 \option{table-caption-short}{<text>} As \code{<short>} in \lstinline=\caption[<short>]{<text>}=.
 \option{table-label}{<text>} The label to refer to the table with \lstinline=\ref=
   and similar commands. Default = \code{tab:ghs-hp-statements}
 \option{table-row-sep}{<dim>} The separation of the table rows. A \TeX\ dimension.
   Default = \code{3pt}
 \option{table-rules}{\default{default}|booktabs|none} The style of the horizontal
   rules in the table. \code{default} uses \lstinline=\hline=, \code{booktabs} uses
   \lstinline=\toprule=, \lstinline=\midrule= or \lstinline=\bottomrule=, resp.
   This option needs the \paket{booktabs} package which you have to load yourself
   then. Default = \code{default}
 \option{table-top-head-rule}{\default{default}|booktabs|none} Change top rule
   explicitly. Default = \code{default}
 \option{table-head-rule}{\default{default}|booktabs|none} Change rule below head
   explicitly. Default = \code{default}
 \option{table-foot-rule}{\default{default}|booktabs|none} Change foot rule
   explicitly. Default = \code{default}
 \option{table-last-foot-rule}{\default{default}|booktabs|none} Change last foot
   rule explicitly. Default = \code{default}
\end{beschreibung}

The code below shows how table~\ref{tab:ghs-hp-statements} was created: 
\begin{beispiel}[code only]
 \ghslistall[fill-in,table-rules=booktabs]
\end{beispiel}

\ghslistall[fill-in,table-rules=booktabs]
\secidx*{List of All Statements}\secidx*{GHSYSTEM}

\appendix
\part{Appendix}\index{APPENDIX@\textbf{APPENDIX}}
\addsec{Overview: Options and Customization}\label{sec:overview}\secidx{Option Overview (chemmacros)}
\minisec{Options}
In the table below all options provided by \chemmacros for customization are listed.
All options that belong to a module can be set with 
\begin{beschreibung}
 \Befehl{chemsetup}[<module>]{<keyval>} or
 \Befehl{chemsetup}{<module>/<keyval>}.
\end{beschreibung}
Some options can be set without value. Then the \default{underlined} value is used.
The options belonging to the modules \code{\textcolor{module}{chemformula}} and
\code{\textcolor{module}{ghsystem}} are not listed here.
\small
\begin{longtable}{>{\ttfamily\color{key}\hspace{5mm}}l>{\ttfamily\color{module}}l>{\ttfamily}l>{\ttfamily}ll}
 \toprule
  \normalfont\normalcolor\bfseries option &
  \normalfont\normalcolor\bfseries module &
  \normalfont\bfseries values &
  \normalfont\bfseries default & \\
 \midrule
 \endhead
 \bottomrule
 \endfoot
 \multicolumn{5}{l}{package options:} \\
 bpchem              & option   & \default{true}|false       & false                 & page~\pageref{key:option_bpchem} \\
 circled             & option   & formal|\default{all}|none  & formal                & page~\pageref{key:option_circled} \\
 circletype          & option   & chem|math                  & chem                  & page~\pageref{key:option_circletype} \\
 cmversion           & option   & 1|2|bundle                 & bundle                & page~\pageref{key:option_cmversion} \\
 ghsystem            & option   & \default{true}|false       & true                  & page~\pageref{key:option_ghsystem} \\
 iupac               & option   & auto|restricted|strict     & auto                  & page~\pageref{key:option_iupac} \\
 language            & option   & <language>                 & english               & page~\pageref{key:option_language} \\
 method              & option   & chemformula|mhchem         & chemformula           & page~\pageref{key:option_method} \\
 Nu                  & option   & chemmacros|mathspec        & chemmacros            & page~\pageref{key:option_Nu} \\
 strict              & option   & \default{true}|false       & false                 & page~\pageref{key:option_strict} \\
 synchronize         & option   & \default{true}|false       & false                 & page~\pageref{key:option_synchronize} \\
 greek               & option   & math|textgreek|\default{upgreek} & upgreek         & page~\pageref{key:option_greek} \\
 xspace              & option   & \default{true}|false       & true                  & page~\pageref{key:option_xspace} \\
 \multicolumn{5}{l}{\cmd{ba}, \cmd{Nu}:} \\
 elpair              & particle & \default{dots}|dash|false  & false                 & page~\pageref{key:particle_elpair} \\
 \multicolumn{5}{l}{\ac{iupac} commands:} \\
 break-space         & iupac    & <dim>                      & .01em                 & page~\pageref{key:iupac_break-space} \\
 bridge-number       & iupac    & sub|super                  & sub                   & page~\pageref{key:iupac_bridge-number} \\
 cip-kern            & iupac    & <dim>                      & .075em                & page~\pageref{key:iupac_cip-kern} \\
 coord-use-hyphen    & iupac    & \default{true}|false       & true                  & page~\pageref{key:iupac_coord-use-hyphen} \\
 hyphen-pre-space    & iupac    & <dim>                      & .01em                 & page~\pageref{key:iupac_hyphen-pre-space} \\
 hyphen-post-space   & iupac    & <dim>                      & -.03em                & page~\pageref{key:iupac_hyphen-post-space} \\
 \multicolumn{5}{l}{\cmd{DeclareChemLatin}:} \\
 format              & latin    & <anything>                 & \lstinline=\itshape=  & page~\pageref{key:latin_format} \\
 \multicolumn{5}{l}{\cmd{pch}, \cmd{mch}, \cmd{fpch}, \cmd{fmch}:} \\
 append              & charges  & \default{true}|false       & false                 & page~\pageref{key:charges_append} \\
 \multicolumn{5}{l}{acid/base:} \\
 p-style             & acid-base & slanted|italics|upright   & upright               & page~\pageref{key:acid-base_p-style} \\
 \multicolumn{5}{l}{\cmd{ox}:} \\
 align               & ox       & center|right               & center                & page~\pageref{key:ox_align} \\
 parse               & ox       & \default{true}|false       & true                  & page~\pageref{key:ox_parse} \\
 roman               & ox       & \default{true}|false       & true                  & page~\pageref{key:ox_roman} \\
 pos                 & ox       & top|super|side             & top                   & page~\pageref{key:ox_pos} \\
 explicit-sign       & ox       & \default{true}|false       & false                 & page~\pageref{key:ox_explicit-sign} \\
 decimal-marker      & ox       & comma|point                & point                 & page~\pageref{key:ox_decimal-marker} \\
 \multicolumn{5}{l}{\cmd{OX}, \cmd{redox}:} \\
 dist                & redox    & <dim>                      & .6em                  & page~\pageref{key:redox_dist} \\
 sep                 & redox    & <dim>                      & .2em                  & page~\pageref{key:redox_sep} \\
 \multicolumn{5}{l}{\cmd{Enthalpy}, \cmd{Entropy}, \cmd{Gibbs}:} \\
 exponent            &          & <anything>                 & \cmd{standardstate}   & page~\pageref{key:none_exponent} \\
 delta               &          & <anything>|false           &                       & page~\pageref{key:none_delta} \\
 subscript           &          & left|right                 &                       & page~\pageref{key:none_subscript} \\
 unit                &          & <unit>                     &                       & page~\pageref{key:none_unit} \\
 \multicolumn{5}{l}{\cmd{DeclareChemState}, \cmd{RenewChemState}:} \\
 exponent            &          & <anything>                 & \cmd{standardstate}   & page~\pageref{key:none_exponent} \\
 delta               &          & <anything>|false           &                       & page~\pageref{key:none_delta} \\
 subscript           &          & <anything>                 &                       & page~\pageref{key:none_subscript} \\
 subscript-left      &          & \default{true}|false       &                       & page~\pageref{key:none_subscript-left} \\
 \multicolumn{5}{l}{\cmd{State}:} \\
 exponent            & state    & <anything>                 & \cmd{standardstate}   & page~\pageref{key:state_exponent} \\
 delta               & state    & <anything>|false           &                       & page~\pageref{key:state_delta} \\
 subscript-left      & state    & \default{true}|false       &                       & page~\pageref{key:state_subscript-left} \\
 \multicolumn{5}{l}{\cmd{NMR}:} \\
 unit                & nmr      & <unit>                     & \cmd{mega}\cmd{hertz} & page~\pageref{key:nmr_unit} \\
 nucleus             & nmr      & \{<num>,<atom symbol>\}    & \{1,H\}               & page~\pageref{key:nmr_nucleus} \\
 format              & nmr      & <anything>                 &                       & page~\pageref{key:nmr_format}  \\
 pos-number          & nmr      & side|sub                   & side                  & page~\pageref{key:nmr_pos-number}  \\
 coupling-unit       & nmr      & <unit>                     & \lstinline+\hertz+    & page~\pageref{key:nmr_coupling-unit}  \\
 parse               & nmr      & \default{true}|false       & true                  & page~\pageref{key:nmr_parse}  \\
 delta               & nmr      & <anything>                 &                       & page~\pageref{key:nmr_delta}  \\
 list                & nmr      & \default{true}|false       & false                 & page~\pageref{key:nmr_list}  \\
 list-setup          & nmr      &                            & see text              & page~\pageref{key:nmr_list-setup}  \\
 use-equal           & nmr      & \default{true}|false       & true                  & page~\pageref{key:nmr_use-equal}  \\
 \multicolumn{5}{l}{\cmd{DeclareChemReaction}:} \\
 star                &          & \default{true}|false       & false                 & page~\pageref{key:none_star} \\
 arg                 &          & \default{true}|false       & false                 & page~\pageref{key:none_arg} \\
 list-name           & reaction & <anything>                 & List of reactions     & page~\pageref{key:reaction_list-name} \\
 list-entry          & reaction & <anything>                 & Reaction              & page~\pageref{key:reaction_list-entry} \\
 \multicolumn{5}{l}{\cmd{mhName}:} \\
 align               & mhName   & <alignment>                & \cmd{centering}       & page~\pageref{key:mhName_align} \\
 format              & mhName   & <commands>                 &                       & page~\pageref{key:mhName_format} \\
 fontsize            & mhName   & <fontsize>                 & \cmd{tiny}            & page~\pageref{key:mhName_fontsize} \\
 width               & mhName   & <dim>                      &                       & page~\pageref{key:mhName_width} \\
 \multicolumn{5}{l}{phases:} \\
 pos                 & phases   & side|sub                   & side                  & page~\pageref{key:phases_pos} \\
 space               & phases   & <dim>                      & .1333em               & page~\pageref{key:phases_space} \\
 \multicolumn{5}{l}{\cmd{newman}:} \\
 angle               & newman   & <angle>                    & 0                     & page~\pageref{key:newman_angle} \\
 scale               & newman   & <factor>                   & 1                     & page~\pageref{key:newman_scale} \\
 ring                & newman   & <tikz>                     &                       & page~\pageref{key:newman_ring} \\
 atoms               & newman   & <tikz>                     &                       & page~\pageref{key:newman_atoms} \\
 back-atoms          & newman   & <tikz>                     &                       & page~\pageref{key:newman_back-atoms} \\
 \multicolumn{5}{l}{\cmd{orbital} \ttfamily <type> = s|p|sp|sp2|sp3:} \\
 phase               & orbital/<type>  & +|-                 & +                     & page~\pageref{key:orbital_phase} \\
 scale               & orbital/<type>  & <factor>            & 1                     & page~\pageref{key:orbital_scale} \\
 color               & orbital/<type>  & <color>             & black                 & page~\pageref{key:orbital_color} \\
 angle               & orbital/<type>  & <angle>             & 90                    & page~\pageref{key:orbital_angle} \\
 half                & orbital/p       & \default{true}|false & false                & page~\pageref{key:orbital_half} \\
 overlay             & orbital  & \default{true}|false       & false                 & page~\pageref{key:orbital_overlay} \\
 opacity             & ornital  & <num>                      & 1                     & page~\pageref{key:orbital_opacity}
\end{longtable}
\normalsize

\minisec{Commands}
Quite a number of commands has been presented with which the possibilities of
\chemmacros can be expanded. They are listed below for a quick overview.
\begin{beschreibung}
 \befehl{DeclareChemArrow} Define new arrow, see
   page~\pageref{cmd:DeclareChemArrow}.
 \befehl{RenewChemArrow} Redefine existing arrow.
 \befehl{DeclareChemBond} Define a bond, see
   page~\pageref{cmd:DeclareChemBond}.
 \befehl{RenewChemBond} Redefine a bond.
 \befehl{DeclareChemBondAlias} Declare an alias to an existing bond.
 \befehl{DeclareChemIUPAC} Define new \ac{iupac} command, see
   page~\pageref{cmd:DeclareChemIUPAC}.
 \befehl{RenewChemIUPAC} Redefine \ac{iupac} command.
 \befehl{DeclareChemLatin} Define new latin phrases, see
   page~\pageref{cmd:DeclareChemLatin}.
 \befehl{RenewChemLatin} Redefine latin phrases.
 \befehl{DeclareChemNMR} Define new NMR command, see
   page~\pageref{cmd:DeclareChemNMR}.
 \befehl{RenewChemNMR} Redefine NMR command.
 \befehl{DeclareChemParticle} Define new particle, see
   page~\pageref{cmd:DeclareChemParticle}.
 \befehl{RenewChemParticle} Redefine particle.
 \befehl{DeclareChemPhase} Define new phases command, see
   page~\pageref{cmd:DeclareChemPhase}.
 \befehl{RenewChemPhase} Redefine phases command.
 \befehl{DeclareChemReaction} Define new reaction environment, see
   page~\pageref{cmd:DeclareChemReaction}.
 \befehl{DeclareChemState} Define new state command, see
   page~\pageref{cmd:DeclareChemState}.
 \befehl{RenewChemState} Redefine state command.
\end{beschreibung}
\secidx*{Option Overview (chemmacros)}

\addsec{Suggestions and Bug Reports}\addcontentsline{toc}{section}{Suggestions and Bug Reports}
Feedback on \chemmacros, \chemformula and \ghsystem is highly appreciated and
welcome! Especially \chemformula and \ghsystem are still in beta testing phase
so even if I repeat myself: feedback is highly welcome.

If you have suggestions for macros, missing features \etc, please don't hesitate
to contact me. If you recognize any errors, be it chemical ones, wrong documentation
and the like, I'd be grateful about a short email%
\footnote{\href{mailto:contact@mychemistry.eu}{contact@mychemistry.eu}}.

If you find any bugs, it would be best, if you'd send me a minimal example, with
which I can reproduce the bug. You can also submit an issue on
\url{https://bitbucket.org/cgnieder/chemmacros/} instead.

Many thanks to all the people who already provided me with feedback, especially
(in alphabetical order):
\begin{itemize}
 \item \href{http://www.mathannotated.com/}{Peter Cao}
 \item Christina Lüdigk
 \item Dr.\ Paul King
 \item Jonas Rivetti (Special thanks for his translation of the hazard and
   precautionary statements into Italian!)
 \item Christoph Schäfer
 \item Timo Stein
\end{itemize}

{\EmbracOff\printbibliography}

{\catcode`\^=11 \catcode`\#=11
\printindex}

% \listoftodos
\end{document}