chemmacros (10apr14)

git-svn-id: svn://tug.org/texlive/trunk@33447 c570f23f-e606-0410-a88d-b1316a301751

10 files changed, 451 insertions, 91 deletions

diff --git a/Master/texmf-dist/doc/latex/chemmacros/README b/Master/texmf-dist/doc/latex/chemmacros/README
index 48b53adb453..11ca389c3b7 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/README
+++ b/Master/texmf-dist/doc/latex/chemmacros/README
@@ -1,8 +1,8 @@
 --------------------------------------------------------------------------
-the CHEMMACROS bundle 2014/01/29
- - chemmacros package v4.4   -> macros and commands for chemists
- - chemformula package v4.4  -> typeset chemical compounds and reactions
- - ghsystem package v4.2e    -> typeset H & P statements and pictograms
+the CHEMMACROS bundle 2014/04/08
+ - chemmacros package v4.5   -> macros and commands for chemists
+ - chemformula package v4.5  -> typeset chemical compounds and reactions
+ - ghsystem package v4.5     -> typeset H & P statements and pictograms
                                 from the globally harmonised system (GHS)
  - chemgreek package v0.4    -> handle mapping of upright greek letters to
                                 the \chemalpha ... commands
diff --git a/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.pdf b/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.pdf
index 6ac302eab5b..c1e6ba8075d 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.pdf
+++ b/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.pdf
diff --git a/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.tex b/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.tex
index 36ff900a1fa..00ebc3d13d8 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.tex
+++ b/Master/texmf-dist/doc/latex/chemmacros/chemformula_en.tex
@@ -803,7 +803,7 @@ right.
 \end{example}
 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}.
+be set with the option \option{charge-hshift}.
 \begin{example}
   \ch{SO4^2-} \ch{NH4+} \ch{Na+} \par
   \chemsetup[chemformula]{charge-hshift=.5ex}
@@ -1015,10 +1015,16 @@ There are various different types:
     stoichiometric equation
   \command{ch}[\Marg{ <=> } \ch{<=>}]
     equilibrium arrow
+  \command{ch}[\Marg{ >=< } \ch{>=<}]
+    reversed equilibrium arrow
   \command{ch}[\Marg{ <=>> } \ch{<=>>}]
     unbalanced equilibrium arrow to the right
+  \command{ch}[\Marg{ >=<< } \ch{>=<<}]
+    reversed unbalanced equilibrium arrow to the right
   \command{ch}[\Marg{ <<=> } \ch{<<=>}]
     unbalanced equilibrium arrow to the left
+  \command{ch}[\Marg{ >>=< } \ch{>>=<}]
+    reversed unbalanced equilibrium arrow to the left
   \command{ch}[\Marg{ <o> } \ch{<o>}]
     isolobal arrow
 \end{commands}
@@ -1456,6 +1462,52 @@ The next example shows the effect of some of the options:
   }
 \end{example}
 
+\section{Kröger-Vink Notation}\label{sec:kroger-vink-notation}
+
+\chemformula\ also supports the Kröger-Vink notation\sinceversion{4.5}.
+\begin{options}
+  \keybool{kroeger-vink}\Default{false}
+    Enable the Kröger-Vink notation. As most options this can be enabled
+    globally via the setup command or locally as option to \cs{ch}.
+\end{options}
+
+With this option enabled several changes come into effect: \code{'} prodoces a
+prime, a \code{x} in a superscript produces $\times$, and both a \code{.} and
+a \code{*} produce a little filled circle. In the Kröger-Vink notation a prime
+denotes a negative relative charge, the circle a positive relative charge, and
+the cross denotes a neutral relative charge.
+
+\begin{example}[side-by-side]
+  \setchemformula{kroeger-vink=true}
+  \ch{Al_{Al}^'}
+  \ch{Al_{Al}'}\par
+  \ch{Ni_{Cu}^{x}}\par
+  \ch{V_{Cl}^.}
+  \ch{V_{Cl}^*}\par
+  \ch{Ca_i^{..}}\par
+  \ch{e^'}\par
+  \ch{Cl_i^{''}}
+  \ch{Cl_i''}\par
+  \ch{O_i^{''}}
+  \ch{O_i''}
+\end{example}
+
+There are a number of options for customizations:
+\begin{options}
+  \keyval{kv-positive-style}{\TikZ}\Default
+    \TikZ\ code for positive charge dot.
+  \keyval{kv-positive-radius}{dim}\Default{.3ex}
+    Radius of positive charge dot
+  \keyval{kv-positive-hshift}{dim}\Default{.15em}
+    Horizontal shift of positive charge dot
+  \keyval{kv-positive-vshift}{dim}\Default{.5ex}
+    Vertical shift positive charge dot
+  \keyval{kv-positive-offset}{dim}\Default{.4em}
+    The offset of two consecutive positive charge dots
+  \keyval{kv-neutral-symbol}{\TeX\ code}\Default{\$\cs*{times}\$}
+    Symbol for neutral particles.
+\end{options}
+
 \section{Further Examples}
 This section presents some examples of a possible usage.
 
diff --git a/Master/texmf-dist/doc/latex/chemmacros/chemgreek_en.pdf b/Master/texmf-dist/doc/latex/chemmacros/chemgreek_en.pdf
index b25f82c8f41..2bc8bcd89d8 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/chemgreek_en.pdf
+++ b/Master/texmf-dist/doc/latex/chemmacros/chemgreek_en.pdf
diff --git a/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.pdf b/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.pdf
index 31851b59554..cb13c1ad0ea 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.pdf
+++ b/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.pdf
diff --git a/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.tex b/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.tex
index 517d55d2ea8..bc5bcc0d24e 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.tex
+++ b/Master/texmf-dist/doc/latex/chemmacros/chemmacros_en.tex
@@ -425,6 +425,12 @@ With version~4.0 some changes have been made:
   \item New \module{nmr} option \option{coupling-pos-cs}.
 \end{itemize}
 
+\subsection{Version 4.5}
+\begin{itemize}
+  \item New \module{acid-base} option \option{subscript}.
+  \item Dutch translations.
+\end{itemize}
+
 \section{Package Options}\label{sec:options}
 \chemmacros\ has several package options. They all are used as key/value pairs
 like
@@ -1178,6 +1184,9 @@ There is one option which changes the style the \p{} is typeset:
     The subscript to \cs{Kb} and \cs{pKb}.
   \keyval{K-water}{text}\Module{acid-base}\Default{W}
     The subscript to \cs{Kw}.
+  \keychoice{subscript}{lowercase,uppercase}\Module{acid-base}\Default{uppercase}
+    Choose\sinceversion{4.5} if the default subscript is written in lower- or
+    uppercase.
 \end{options}
 \begin{example}
   \pH, \pKa \par
diff --git a/Master/texmf-dist/doc/latex/chemmacros/ghsystem_en.pdf b/Master/texmf-dist/doc/latex/chemmacros/ghsystem_en.pdf
index 288abb1dacf..f52b8a18b42 100644
--- a/Master/texmf-dist/doc/latex/chemmacros/ghsystem_en.pdf
+++ b/Master/texmf-dist/doc/latex/chemmacros/ghsystem_en.pdf
diff --git a/Master/texmf-dist/tex/latex/chemmacros/chemformula.sty b/Master/texmf-dist/tex/latex/chemmacros/chemformula.sty
index 3774338595f..b88a3f8a315 100644
--- a/Master/texmf-dist/tex/latex/chemmacros/chemformula.sty
+++ b/Master/texmf-dist/tex/latex/chemmacros/chemformula.sty
@@ -27,8 +27,8 @@
 % --------------------------------------------------------------------------
 \RequirePackage{ expl3 , xparse , l3keys2e , tikz , amsmath , xfrac , nicefrac , scrlfile }
 \usetikzlibrary{arrows}
-\def\chemformula@version{4.4}
-\def\chemformula@date{2014/01/29}
+\def\chemformula@version{4.5}
+\def\chemformula@date{2014/04/08}
 
 \ProvidesExplPackage
   {chemformula}
@@ -136,6 +136,7 @@
 \cs_generate_variant:Nn \tl_if_in:nnT      { x , nV }
 \cs_generate_variant:Nn \prop_get:Nn       { NV }
 \cs_generate_variant:Nn \tl_set_rescan:Nnn { NnV }
+\cs_generate_variant:Nn \dim_set:Nn        { NV }
 
 % --------------------------------------------------------------------------
 % package options:
@@ -218,17 +219,16 @@
 \bool_new:N      \l__chemformula_charge_full_shift_bool
 \bool_new:N      \l__chemformula_tikzexternaldisable_bool
 \bool_set_true:N \l__chemformula_tikzexternaldisable_bool
+\bool_new:N      \l__chemformula_kroegervink_bool
 
 % dimensions:
 \dim_new:N  \l__chemformula_arrow_length_dim
+\dim_new:N  \l__chemformula_arrow_label_height_dim
 \dim_new:N  \l__chemformula_arrow_label_offset_dim
 \dim_set:Nn \l__chemformula_arrow_label_offset_dim { 2pt }
 \dim_new:N  \l__chemformula_arrow_minimum_length_dim
 \dim_new:N  \l__chemformula_arrow_shortage_dim
 \dim_new:N  \l__chemformula_arrow_offset_dim
-\dim_set:Nn \l__chemformula_arrow_offset_dim { .75em }
-\dim_new:N  \l__chemformula_compound_sep_dim
-\dim_set:Nn \l__chemformula_compound_sep_dim { .5em }
 \dim_new:N  \l__chemformula_arrow_yshift_dim
 \dim_set:Nn \l__chemformula_arrow_yshift_dim { 0pt }
 \dim_new:N  \l__chemformula_radical_radius_dim
@@ -238,7 +238,7 @@
 \dim_new:N  \l__chemformula_radical_vshift_dim
 \dim_set:Nn \l__chemformula_radical_vshift_dim { .5ex }
 \dim_new:N  \l__chemformula_radical_space_dim
-\dim_set:Nn \l__chemformula_radical_space_dim { .15em }
+\dim_set:Nn \l__chemformula_radical_space_dim { .3em }
 \dim_new:N  \l__chemformula_arrow_head_dim
 \dim_new:N  \l__chemformula_name_dim
 \dim_new:N  \l__chemformula_adduct_space_dim
@@ -261,6 +261,14 @@
 \dim_set:Nn \l__chemformula_elspec_pair_line_length_dim { 1.5ex }
 \dim_new:N  \l__chemformula_elspec_pair_width_dim
 \dim_set:Nn \l__chemformula_elspec_pair_width_dim { 1pt }
+\dim_new:N  \l__chemformula_kroegervink_positive_radius_dim
+\dim_set:Nn \l__chemformula_kroegervink_positive_radius_dim { .3ex }
+\dim_new:N  \l__chemformula_kroegervink_positive_hshift_dim
+\dim_set:Nn \l__chemformula_kroegervink_positive_hshift_dim { .15em }
+\dim_new:N  \l__chemformula_kroegervink_positive_vshift_dim
+\dim_set:Nn \l__chemformula_kroegervink_positive_vshift_dim { .5ex }
+\dim_new:N  \l__chemformula_kroegervink_positive_space_dim
+\dim_set:Nn \l__chemformula_kroegervink_positive_space_dim { .4em }
 
 % skips:
 \skip_new:N  \l__chemformula_stoich_space_skip
@@ -276,6 +284,8 @@
 \int_new:N   \g__chemformula_lewis_int
 
 % token lists:
+\tl_new:N     \l__chemformula_compound_sep_tl
+\tl_set:Nn    \l__chemformula_compound_sep_tl { .5em }
 \tl_new:N     \l__chemformula_arrow_ratio_tl
 \tl_set:Nn    \l__chemformula_arrow_ratio_tl { .6 }
 \tl_new:N     \l__chemformula_radical_style_tl
@@ -290,6 +300,8 @@
 \tl_new:N     \l__chemformula_arrow_type_tl
 \tl_new:N     \l__chemformula_arrow_penalty_tl
 \tl_set:Nn    \l__chemformula_arrow_penalty_tl { 0 }
+\tl_new:N     \l__chemformula_arrow_offset_tl
+\tl_set:Nn    \l__chemformula_arrow_offset_tl { .75em }
 \tl_new:N     \l__chemformula_plus_penalty_tl
 \tl_set:Nn    \l__chemformula_plus_penalty_tl { 700 }
 \tl_new:N     \l__chemformula_bond_penalty_tl
@@ -327,6 +339,9 @@
 \tl_new:N     \l__chemformula_elspec_default_type_tl
 \tl_set:Nn    \l__chemformula_elspec_default_type_tl { pair }
 \tl_const:Nx  \c_chemformula_colon_tl { \token_to_str:N : }
+\tl_new:N     \l__chemformula_kroegervink_positive_style_tl
+\tl_new:N     \l__chemformula_kroegervink_neutral_tl
+\tl_set:Nn    \l__chemformula_kroegervink_neutral_tl { $\times$ }
 
 % property lists:
 \prop_new:N \l__chemformula_arrows_code_prop
@@ -337,6 +352,7 @@
 \prop_new:N \l__chemformula_numbers_prop
 \prop_new:N \l__chemformula_no_stoich_prop
 \prop_new:N \l__chemformula_lewis_elspec_types_prop
+\prop_new:N \l__chemformula_kroegervink_prop
 
 % sequences:
 \seq_new:N \l__chemformula_arrows_type_seq
@@ -356,7 +372,7 @@
 
 \cs_new:Npn \chemformula_draw:nn #1#2
   { \draw [ #1 ] #2 ;  }
-\cs_generate_variant:Nn \chemformula_draw:nn { xn,nx,xx,xf }
+\cs_generate_variant:Nn \chemformula_draw:nn { xn,nx,xx,xf,Vn }
 
 \cs_new:Npn \chemformula_node:nn #1#2
   { \node [ #1 ] { #2 }  ;  }
@@ -528,20 +544,36 @@
 
 % --------------------------------------------------------------------------
 % Some basic internal commands:
+
+\cs_new_protected:Npn \chemformula_radical_or_decimal:
+  {
+    \peek_meaning:NTF \c_group_begin_token
+      { \chemformula_decimal: }
+      { \chemformula_radical: }
+  }
+
 \cs_new_protected:Npn \chemformula_radical:
   {
-    \chemformula_tikz:xn
+    \hbox_overlap_right:n
       {
-        \l__chemformula_radical_style_tl ,
-        baseline,
-        minimum~height=0pt,
-        inner~sep=0pt,
-        outer~sep=0pt
-      }
-      {
-         \fill (0,0)
-           ++(\l__chemformula_radical_hshift_dim,\l__chemformula_radical_vshift_dim)
-           circle (\l__chemformula_radical_radius_dim) ;
+        \chemformula_tikz:xn
+          {
+            \l__chemformula_radical_style_tl ,
+            baseline ,
+            minimum~ height = 0pt ,
+            minimum~ width = 0pt ,
+            inner~ sep = 0pt ,
+            outer~ sep = 0pt ,
+            overlay
+          }
+          {
+            \fill (0,0)
+              ++(
+                \l__chemformula_radical_hshift_dim ,
+                \l__chemformula_radical_vshift_dim
+              )
+              circle (\l__chemformula_radical_radius_dim) ;
+          }
       }
     \skip_horizontal:N \l__chemformula_radical_space_dim
   }
@@ -567,6 +599,68 @@
 \cs_new_eq:NN \chemformula_star_adduct: \chemformula_adduct:
 
 % --------------------------------------------------------------------------
+% Kroeger-Vink notation
+\cs_new_protected:Npn \chemformula_kroegervink_negative:
+  { \ensuremath { \prime } }
+
+\cs_new_protected:Npn \chemformula_kroegervink_neutral:
+  { \ensuremath { \text {\l__chemformula_kroegervink_neutral_tl } } }
+
+\cs_new_protected:Npn \chemformula_kroegervink_positive:
+  {
+    \hbox_overlap_right:n
+      {
+        \chemformula_tikz:xn
+          {
+            \l__chemformula_kroegervink_positive_style_tl ,
+            baseline ,
+            minimum~ height = 0pt ,
+            minimum~ width = 0pt ,
+            inner~ sep = 0pt ,
+            outer~ sep = 0pt ,
+            overlay
+          }
+          {
+            \fill (0,0)
+              ++(
+                \l__chemformula_kroegervink_positive_hshift_dim ,
+                \l__chemformula_kroegervink_positive_vshift_dim
+              )
+              circle (\l__chemformula_kroegervink_positive_radius_dim) ;
+          }
+      }
+    \skip_horizontal:N \l__chemformula_kroegervink_positive_space_dim
+  }
+
+\cs_new:Npn \chemformula_prime:
+  {
+    \bool_if:NTF \l__chemformula_kroegervink_bool
+      { \chemformula_kroegervink_negative: }
+      { ' }
+  }
+
+\keys_define:nn { chemmacros / chemformula }
+  {
+    kroeger-vink       .bool_set:N =
+      \l__chemformula_kroegervink_bool ,
+    % TikZ style:
+    kv-positive-style  .tl_set:N   =
+      \l__chemformula_kroegervink_positive_style_tl ,
+    kv-positive-radius .dim_set:N  =
+      \l__chemformula_kroegervink_positive_radius_dim ,
+    % spacing:
+    kv-positive-hshift .dim_set:N  =
+      \l__chemformula_kroegervink_positive_hshift_dim ,
+    kv-positive-vshift .dim_set:N  =
+      \l__chemformula_kroegervink_positive_vshift_dim ,
+    kv-positive-offset .dim_set:N  =
+      \l__chemformula_kroegervink_positive_space_dim ,
+    % symbol:
+    kv-neutral-symbol  .tl_set:N   =
+      \l__chemformula_kroegervink_neutral_tl
+  }
+
+% --------------------------------------------------------------------------
 % ARROW DEFINITION
 % arrow heads:
 
@@ -666,6 +760,7 @@
 % determine length in dependency of labels
 \cs_new_protected:Npn \__chemformula_determine_arrow_length:NN #1#2
   {
+    \dim_set:NV \l__chemformula_arrow_offset_dim \l__chemformula_arrow_offset_tl
     \box_set_eq:NN \l__chemformula_tmpa_box #1
     \dim_set:Nn \l__chemformula_tmpa_dim { \box_wd:N \l__chemformula_tmpa_box }
     \box_set_eq:NN \l__chemformula_tmpa_box #2
@@ -676,8 +771,6 @@
       { \dim_set_eq:NN \l__chemformula_arrow_length_dim \l__chemformula_tmpb_dim }
     \dim_add:Nn \l__chemformula_arrow_length_dim
       { 2\l__chemformula_arrow_offset_dim }
-%    \dim_add:Nn \l__chemformula_arrow_length_dim
-%      { \l__chemformula_arrow_offset_dim }
     \dim_compare:nF
       { \l__chemformula_arrow_length_dim > \l__chemformula_arrow_minimum_length_dim }
       {
@@ -694,6 +787,16 @@
           \dim_ratio:nn { \l__chemformula_arrow_ratio_tl pt } { 1pt }
         ) * 1/2
       }
+    \box_set_eq:NN \l__chemformula_tmpa_box #1
+    \dim_set:Nn \l__chemformula_tmpa_dim
+      { \box_ht:N \l__chemformula_tmpa_box + \box_dp:N \l__chemformula_tmpa_box }
+    \box_set_eq:NN \l__chemformula_tmpa_box #2
+    \dim_set:Nn \l__chemformula_tmpb_dim
+      { \box_ht:N \l__chemformula_tmpa_box + \box_dp:N \l__chemformula_tmpa_box }
+    \box_clear:N \l__chemformula_tmpa_box
+    \dim_compare:nTF { \l__chemformula_tmpa_dim >= \l__chemformula_tmpb_dim }
+      { \dim_set_eq:NN \l__chemformula_arrow_label_height_dim \l__chemformula_tmpa_dim }
+      { \dim_set_eq:NN \l__chemformula_arrow_label_height_dim \l__chemformula_tmpb_dim }
   }
 
 % --------------------------------------------------------------------------
@@ -754,14 +857,14 @@
           { \l__chemformula_arrow_style_tl }
           {
             coordinate (chemformula_arrow_start) (0pt,0pt)
-            ++ ( \l__chemformula_compound_sep_dim , .3432em)
+            ++ ( \l__chemformula_compound_sep_tl , .3432em)
             ++ (0pt,\l__chemformula_arrow_yshift_dim)
             coordinate (cf_arrow_start)
             ++ ( .5 * \dim_use:N \l__chemformula_arrow_length_dim , 0pt)
             coordinate (cf_arrow_mid)
             ++ ( .5 * \dim_use:N \l__chemformula_arrow_length_dim , 0pt)
             coordinate (cf_arrow_end)
-            ++ ( \l__chemformula_compound_sep_dim , 0pt )
+            ++ ( \l__chemformula_compound_sep_tl , 0pt )
             (cf_arrow_start) ++ (\l__chemformula_arrow_shortage_dim , 0pt)
             coordinate (cf_arrow_mid_start)
             (cf_arrow_end) ++ (-\l__chemformula_arrow_shortage_dim , 0pt)
@@ -849,7 +952,7 @@
     \draw[chemarrow,left~cf-]
       ([yshift=-.15ex]cf_arrow_mid_start) -- ([yshift=-.15ex]cf_arrow_mid_end) ;
   }
-\NewChemArrow {<<=>}
+\NewChemArrow { <<=> }
   {
     \draw[chemarrow,-left~cf]
       ([yshift=.15ex]cf_arrow_mid_start) -- ([yshift=.15ex]cf_arrow_mid_end) ;
@@ -863,6 +966,33 @@
     \draw[chemarrow,left~cf-]
       ([yshift=-.15ex]cf_arrow_start) -- ([yshift=-.15ex]cf_arrow_end) ;
   }
+\NewChemArrow { >>=< }
+  {
+    \draw[chemarrow,right~cf-]
+      ([yshift=.15ex]cf_arrow_start) -- ([yshift=.15ex]cf_arrow_end) ;
+    \draw[chemarrow,-right~cf]
+      ([yshift=-.15ex]cf_arrow_mid_start) -- ([yshift=-.15ex]cf_arrow_mid_end) ;
+  }
+\NewChemArrow { >=<< }
+  {
+    \draw[chemarrow,right~cf-]
+      ([yshift=.15ex]cf_arrow_mid_start) -- ([yshift=.15ex]cf_arrow_mid_end) ;
+    \draw[chemarrow,-right~cf]
+      ([yshift=-.15ex]cf_arrow_start) -- ([yshift=-.15ex]cf_arrow_end) ;
+  }
+\NewChemArrow { >=< }
+  {
+    \draw[chemarrow,right~cf-]
+      ([yshift=.15ex]cf_arrow_start) -- ([yshift=.15ex]cf_arrow_end) ;
+    \draw[chemarrow,-right~cf]
+      ([yshift=-.15ex]cf_arrow_start) -- ([yshift=-.15ex]cf_arrow_end) ;
+  }
+\NewChemArrow { <==> }
+  {
+    \draw[chemarrow,double~ equal~ sign~ distance,double,implies-implies]
+      (cf_arrow_start) -- (cf_arrow_end) ;
+    % \node at ([yshift=-.2ex]cf_arrow_mid) { $\Leftrightarrow$ } ;
+  }
 \NewChemArrow { -/> }
   {
     \draw[chemarrow,-cf] (cf_arrow_start) -- (cf_arrow_end) ;
@@ -882,12 +1012,12 @@
 % arrow customization
 \keys_define:nn { chemmacros / chemformula }
   {
-    arrow-offset     .dim_set:N = \l__chemformula_arrow_offset_dim ,
+    arrow-offset     .tl_set:N  = \l__chemformula_arrow_offset_tl ,
     arrow-min-length .dim_set:N = \l__chemformula_arrow_minimum_length_dim ,
     arrow-yshift     .dim_set:N = \l__chemformula_arrow_yshift_dim ,
     arrow-ratio      .tl_set:N  = \l__chemformula_arrow_ratio_tl ,
     label-offset     .dim_set:N = \l__chemformula_arrow_label_offset_dim ,
-    compound-sep     .dim_set:N = \l__chemformula_compound_sep_dim ,
+    compound-sep     .tl_set:N  = \l__chemformula_compound_sep_tl ,
     arrow-style      .tl_set:N  = \l__chemformula_arrow_style_tl ,
     label-style      .tl_set:N  = \l__chemformula_arrow_label_style_tl ,
     arrow-penalty    .tl_set:N  = \l__chemformula_arrow_penalty_tl ,
@@ -941,7 +1071,7 @@
       \tl_if_blank:nTF { #1 }
         { \tl_gclear:N \g__chemformula_options_tl }
         { \tl_gset:Nn  \g__chemformula_options_tl { #1 } }
-      \__chemformula_ch_aux_i:w #2 \\ \q_no_value \q_stop
+      \__chemformula_ch_newline:w #2 \\ \q_no_value \q_stop
     \group_align_safe_end:
     \tl_use:N    \g__chemformula_output_tl
     \tl_gclear:N \g__chemformula_output_tl
@@ -950,60 +1080,85 @@
 
 % Trickery to use \ch inside align environment:
 % bypass \\:
-\cs_new_protected:Npn \__chemformula_ch_aux_i:w #1 \\ #2 \q_stop
+\cs_new_protected:Npn \__chemformula_ch_newline:w #1 \\ #2 \q_stop
   {
-    \__chemformula_ch_aux_ii:w #1 & \q_no_value \q_stop
+    \__chemformula_ch_align:w #1 & \q_no_value \q_stop
     \quark_if_no_value:nF { #2 }
       {
         \tl_gput_right:Nn \g__chemformula_output_tl { \\ }
-        \__chemformula_ch_aux_i:w #2 \q_stop
+        % look for optional argument:
+        \peek_meaning:NTF [
+          { \__chemformula_ch_newline_skip:w }
+          { \__chemformula_ch_newline:w }
+        #2 \q_stop
       }
   }
 
+\cs_new_protected:Npn \__chemformula_ch_newline_skip:w [ #1 ]
+  {
+    \tl_gput_right:Nn \g__chemformula_output_tl { [#1] }
+    \__chemformula_ch_newline:w
+  }
+
 % bypass &:
-\cs_new_protected:Npn \__chemformula_ch_aux_ii:w #1 & #2 \q_stop
+\cs_new_protected:Npn \__chemformula_ch_align:w #1 & #2 \q_stop
   {
-    \__chemformula_ch_aux_iii:w #1 \label{} \q_no_value \q_stop
+    \__chemformula_ch_label:w #1 \label \q_no_value \q_stop
     \quark_if_no_value:nF { #2 }
       {
         \tl_gput_right:Nn \g__chemformula_output_tl { & }
-        \__chemformula_ch_aux_ii:w #2 \q_stop
+        \__chemformula_ch_align:w #2 \q_stop
       } 
   }
 
 % bypass \label:
-\cs_new_protected:Npn \__chemformula_ch_aux_iii:w #1 \label#2 #3 \q_stop
+\cs_new_protected:Npn \__chemformula_ch_label:w #1 \label #2 \q_stop
   {
-    \__chemformula_ch_aux_iv:w #1 \tag{} \q_no_value \q_stop
-    \quark_if_no_value:nF { #3 }
+    \__chemformula_ch_tag:w #1 \tag{} \q_no_value \q_stop
+    \quark_if_no_value:nF { #2 }
       {
-        \tl_gput_right:Nn \g__chemformula_output_tl { \label { #2 } }
-        \__chemformula_ch_aux_iii:w #3 \q_stop
-      } 
+        \tl_gput_right:Nn \g__chemformula_output_tl { \label }
+        \peek_meaning:NTF [ % ]
+          { \__chemformula_ch_label_opt:w }
+          { \__chemformula_ch_label_no_opt:n }
+        #2 \q_stop
+      }
+  }
+
+\cs_new_protected:Npn \__chemformula_ch_label_opt:w [ #1 ] #2
+  {
+    \tl_gput_right:Nn \g__chemformula_output_tl { [{#1}] {#2} }
+    \__chemformula_ch_label:w
+  }
+
+\cs_new_protected:Npn \__chemformula_ch_label_no_opt:n #1
+  {
+    \tl_gput_right:Nn \g__chemformula_output_tl { {#1} }
+    \__chemformula_ch_label:w
   }
 
 % here's something not working when used together with `hyperref'
 % which seems to be related to \nonumber
 % bypass \tag:
-\cs_new_protected:Npn \__chemformula_ch_aux_iv:w #1 \tag#2 #3 \q_stop
+\cs_new_protected:Npn \__chemformula_ch_tag:w #1 \tag#2 #3 \q_stop
   {
-    \__chemformula_ch_aux_v:w #1 \intertext{} \q_no_value \q_stop
+    \__chemformula_ch_intertext:w #1 \intertext{} \q_no_value \q_stop
     \quark_if_no_value:nF { #3 }
       {
         \tl_gput_right:Nn \g__chemformula_output_tl { \protect\tag { #2 } }
-        \__chemformula_ch_aux_iv:w #3 \q_stop
+        \__chemformula_ch_tag:w #3 \q_stop
       } 
   }
 
 % bypass \intertext:
-\cs_new_protected:Npn \__chemformula_ch_aux_v:w #1 \intertext#2 #3 \q_stop
+\cs_new_protected:Npn \__chemformula_ch_intertext:w #1 \intertext#2 #3 \q_stop
   {
     \tl_gput_right:Nn \g__chemformula_output_tl
       { \__chemformula_ch_main:n { #1 } }
     \quark_if_no_value:nF { #3 }
       {
         \tl_gput_right:Nn \g__chemformula_output_tl { \intertext { #2 } }
-        \__chemformula_ch_aux_v:w #3 \q_stop
+        \__chemformula_ch_intertext:w #3 \q_stop
       }
   }
 
@@ -1017,6 +1172,7 @@
   {
     \group_begin:
       \keys_set:nn { chemmacros / chemformula } { #1 }
+      \__chemformula_save_catcodes:
       \__chemformula_sanitize:Nn
         \l__chemformula_chemformula_tmpa_tl
         { #2 }
@@ -1035,7 +1191,14 @@
 % arrow generation & detection
 \cs_new:Npn \__chemformula_generate_arrows:Nn #1#2
   {
-    \tl_set:Nn \l__chemformula_tmpa_tl { #2 }
+    \tl_set_rescan:Nnn \l__chemformula_tmpa_tl
+      {
+        \char_set_catcode_other:N \>
+        \char_set_catcode_other:N \<
+        \char_set_catcode_other:N \-
+        \char_set_catcode_other:N \=
+      }
+      { #2 }
     \seq_map_inline:Nn \l__chemformula_arrows_type_seq
       {
         \tl_replace_all:Nnn \l__chemformula_tmpa_tl
@@ -1050,7 +1213,7 @@
     \bool_set_false:N \l__chemformula_is_arrow_bool
     \prop_map_inline:Nn \l__chemformula_arrows_code_prop
       {
-        \tl_set_rescan:Nnn \l__chemformula_tmpa_tl {} { ##1 }
+        \__chemformula_sanitize:Nn \l__chemformula_tmpa_tl { ##1 }
         \tl_if_in:nVT { #1 } \l__chemformula_tmpa_tl
           { \bool_set_true:N \l__chemformula_is_arrow_bool }
       }
@@ -1123,6 +1286,7 @@
 \prop_put:Nnn \l__chemformula_cmpd_prop { - } { \chemformula_single_bond: }
 \prop_put:Nnn \l__chemformula_cmpd_prop { = } { \chemformula_double_bond: }
 \prop_put:Nnn \l__chemformula_cmpd_prop { + } { \chemformula_triple_bond: }
+\prop_put:Nnn \l__chemformula_cmpd_prop { ' } { \chemformula_prime: }
 
 % numbers
 \prop_put:Nnn \l__chemformula_numbers_prop { 0 } { 0 }
@@ -1149,7 +1313,8 @@
 \prop_put:Nnn \l__chemformula_charge_prop { 9 } { \chemformula_charge_style:n { 9 } }
 \prop_put:Nnn \l__chemformula_charge_prop { + } { \chemformula_plus: }
 \prop_put:Nnn \l__chemformula_charge_prop { - } { \chemformula_minus: }
-\prop_put:Nnn \l__chemformula_charge_prop { . } { \chemformula_radical: }
+\prop_put:Nnn \l__chemformula_charge_prop { . } { \chemformula_radical_or_decimal: }
+\prop_put:Nnn \l__chemformula_charge_prop { , } { \chemformula_decimal: }
 
 % stoichiometric factors
 \prop_put:Nnn \l__chemformula_stoich_prop { 0 } { 0 }
@@ -1162,8 +1327,8 @@
 \prop_put:Nnn \l__chemformula_stoich_prop { 7 } { 7 }
 \prop_put:Nnn \l__chemformula_stoich_prop { 8 } { 8 }
 \prop_put:Nnn \l__chemformula_stoich_prop { 9 } { 9 }
-\prop_put:Nnn \l__chemformula_stoich_prop { . } { { \l__chemformula_decimal_output_tl } }
-\prop_put:Nnn \l__chemformula_stoich_prop { , } { { \l__chemformula_decimal_output_tl } }
+\prop_put:Nnn \l__chemformula_stoich_prop { . } { \chemformula_decimal: }
+\prop_put:Nnn \l__chemformula_stoich_prop { , } { \chemformula_decimal: }
 \prop_put:Nnn \l__chemformula_stoich_prop { / } { / }
 \prop_put:Nnn \l__chemformula_stoich_prop { _ } { _ }
 \prop_put:Nnn \l__chemformula_stoich_prop { ( } { ( }
@@ -1176,6 +1341,25 @@
 \prop_put:Nnn \l__chemformula_no_stoich_prop { ( } { }
 \prop_put:Nnn \l__chemformula_no_stoich_prop { ) } { }
 
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 0 } { \chemformula_charge_style:n { 0 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 1 } { \chemformula_charge_style:n { 1 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 2 } { \chemformula_charge_style:n { 2 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 3 } { \chemformula_charge_style:n { 3 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 4 } { \chemformula_charge_style:n { 4 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 5 } { \chemformula_charge_style:n { 5 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 6 } { \chemformula_charge_style:n { 6 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 7 } { \chemformula_charge_style:n { 7 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 8 } { \chemformula_charge_style:n { 8 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { 9 } { \chemformula_charge_style:n { 9 } }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { + } { \chemformula_plus: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { - } { \chemformula_minus: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { . } { \chemformula_radical_or_decimal: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { , } { \chemformula_decimal: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { ' } { \chemformula_kroegervink_negative: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { x } { \chemformula_kroegervink_neutral: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { * } { \chemformula_kroegervink_positive: }
+\prop_put:Nnn \l__chemformula_kroegervink_prop { . } { \chemformula_kroegervink_positive: }
+
 % --------------------------------------------------------------------------
 % bonds:
 \cs_new:Npn \chemformula@bondlength
@@ -1380,6 +1564,7 @@
 % remove double or nested sub- and superscripts
 \cs_new_protected:Npn \chemformula_subscript:n #1
   {
+    \chemformula_nobreak:
     \tl_if_eq:nnTF { #1 }{ \chemformula_superscript:n }
       { \__chemformula_subscript:n }
       {
@@ -1476,6 +1661,7 @@
 % remove double or nested sub- and superscripts
 \cs_new_protected:Npn \chemformula_superscript:n #1
   {
+    \chemformula_nobreak:
     \tl_if_eq:nnTF { #1 } { \chemformula_superscript:n }
       { \__chemformula_superscript:n }
       {
@@ -1520,11 +1706,30 @@
     \tl_replace_all:Nnn \l__chemformula_superscript_tl
       { + } { \chemformula_plus: }
     \tl_replace_all:Nnn \l__chemformula_superscript_tl
-      { \chemformula_adduct: } { \chemformula_radical: }
-    \tl_replace_all:Nnn \l__chemformula_superscript_tl
-      { \chemformula_star_adduct: } { * }
-    \tl_replace_all:Nnn \l__chemformula_superscript_tl
-      { . } { \chemformula_radical: }
+      { \chemformula_adduct: } { \chemformula_radical_or_decimal: }
+    \bool_if:NTF \l__chemformula_kroegervink_bool
+      {
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { ' } { \chemformula_kroegervink_negative: }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { \chemformula_adduct: } { . }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { \chemformula_star_adduct: } { * }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { \chemformula_radical_or_decimal: } { . }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { \chemformula_prime: } { \chemformula_kroegervink_negative: }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { * } { \chemformula_kroegervink_positive: }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { . } { \chemformula_kroegervink_positive: }
+      }
+      {
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { \chemformula_star_adduct: } { * }
+        \tl_replace_all:Nnn \l__chemformula_superscript_tl
+          { . } { \chemformula_radical_or_decimal: }
+      }
   }
 
 \cs_new_protected:Npn \__chemformula_superscript_raise:N #1
@@ -1551,10 +1756,19 @@
         {
           \c_math_toggle_token
             \scriptstyle
-            \prop_get:NoNTF \l__chemformula_charge_prop
-               { #1 } \l__chemformula_tmpa_tl
-              { \tl_use:N \l__chemformula_tmpa_tl }
-              { \chemformula_charge_style:n { #1 } }
+            \bool_if:NTF \l__chemformula_kroegervink_bool
+              {
+                \prop_get:NoNTF \l__chemformula_kroegervink_prop
+                  { #1 } \l__chemformula_tmpa_tl
+                  { \tl_use:N \l__chemformula_tmpa_tl }
+                  { \chemformula_charge_style:n { #1 } }
+              }
+              {
+                \prop_get:NoNTF \l__chemformula_charge_prop
+                  { #1 } \l__chemformula_tmpa_tl
+                  { \tl_use:N \l__chemformula_tmpa_tl }
+                  { \chemformula_charge_style:n { #1 } }
+              }
           \c_math_toggle_token
         }
     \group_end:
@@ -1581,6 +1795,12 @@
         \bool_set_false:N \l__chemformula_charge_full_shift_bool
         \dim_zero:N \l__chemformula_charge_shift_dim
       }
+    % no shift for Kroeger Vink notation
+    \bool_if:NT \l__chemformula_kroegervink_bool
+      {
+        \bool_set_false:N \l__chemformula_charge_full_shift_bool
+        \dim_zero:N \l__chemformula_charge_shift_dim
+      }
     % align to the right if isotope else to the left
     \bool_if:NTF \l__chemformula_is_isotope_bool
       {
@@ -1666,6 +1886,7 @@
 % read the input
 \cs_new_protected:Npn \chemformula_input:n #1
   {
+    \__chemformula_save_catcodes:
     \__chemformula_sanitize:Nn \l__chemformula_chemformula_tmpa_tl { #1 }
     \chemformula_input_escape_text:V \l__chemformula_chemformula_tmpa_tl
     \chemformula_input_escape_math:n { #1 }
@@ -1703,6 +1924,8 @@
 
 % --------------------------------------------------------------------------
 % input stoichiometric factors
+\cs_new:Npn \chemformula_decimal: { { \l__chemformula_decimal_output_tl } }
+
 \cs_new_protected:Npn \chemformula_input_stoich:n #1
   {
     \bool_set_true:N \l__chemformula_stoich_bool
@@ -1779,7 +2002,7 @@
   {
     % get head:
     \tl_set:Nx \l__chemformula_tmpa_tl { \tl_head:n { #1 } }
-    \tl_set:Nn \l__chemformula_tmpb_tl { \l__chemformula_decimal_output_tl }
+    \tl_set:Nn \l__chemformula_tmpb_tl { \chemformula_decimal: }
     % check if stoich starts with decimal-marker and add leading 0 if so:
     \tl_if_eq:NNTF \l__chemformula_tmpa_tl \l__chemformula_tmpb_tl
       { \tl_put_right:Nn \l__chemformula_input_tl { 0#1 } }
@@ -1907,7 +2130,7 @@
         \tl_clear:N \l__chemformula_stoich_tl
       }
   }
-\cs_generate_variant:Nn \chemformula_input_cmpd:nN { VN }
+\cs_generate_variant:Nn \chemformula_input_cmpd:nN { V }
 
 \cs_new_protected:Npn \chemformula_font_inner:
   {
@@ -1940,7 +2163,7 @@
 \cs_new:Npn \__chemformula_fontspec_aux:w [#1]#2 \q_stop
   { \newfontfamily \chemformula_font: [ #1 ] { #2 } }
 
-\cs_new_protected:Npn \__chemformula_sanitize:Nn #1#2
+\cs_new_protected:Npn \__chemformula_save_catcodes:
   {
     \cs_gset_protected:Npx \__chemformula_restore:
       {
@@ -1952,7 +2175,13 @@
         \char_set_catcode:nn {  35 } { \char_value_catcode:n {  35 } }% #
         \char_set_catcode:nn {  33 } { \char_value_catcode:n {  33 } }% !
         \char_set_catcode:nn {  34 } { \char_value_catcode:n {  34 } }% "
+        \char_set_catcode:nn {  60 } { \char_value_catcode:n {  60 } }% <
+        \char_set_catcode:nn {  62 } { \char_value_catcode:n {  62 } }% >
       }
+  }
+
+\cs_new_protected:Npn \__chemformula_sanitize:Nn #1#2
+  {
     \tl_set_rescan:Nnn #1
       {
         % expl3 catcodes:
@@ -1964,11 +2193,15 @@
         \char_set_catcode_letter:N \{
         \char_set_catcode_letter:N \}
         % this one seems not necessary any more:
-%        \char_set_catcode_letter:N \\
+        % \char_set_catcode_letter:N \\
         \char_set_catcode_letter:N \#
         % make the naming work with babel languages like French that make
         % ! active:
         \char_set_catcode_other:N  \!
+        % make the naming work with babel languages like Spanish that make
+        % < and > active:
+        \char_set_catcode_other:N \>
+        \char_set_catcode_other:N \<
         % ensure " is other:
         \char_set_catcode_other:N \"
       }
@@ -2041,17 +2274,23 @@
                   }
                   {
                     \prop_get:NnNTF \l__chemformula_cmpd_prop { ##1 } \l__chemformula_tmpb_tl
-                      { \tl_put_right:No #2 { \l__chemformula_tmpb_tl } }
+                      { \tl_put_right:NV #2 \l__chemformula_tmpb_tl }
                       { \tl_put_right:Nn #2 { ##1 } }
                   }
               }
           }
           {
             \prop_get:NnNTF \l__chemformula_cmpd_prop { ##1 } \l__chemformula_tmpb_tl
-              { \tl_put_right:No #2 { \l__chemformula_tmpb_tl } }
+              { \tl_put_right:NV #2 \l__chemformula_tmpb_tl }
               { \tl_put_right:Nn #2 { ##1 } }
           }
       }
+    \bool_if:NT \l__chemformula_kroegervink_bool
+      {
+        \tl_replace_all:Nnn #2
+          { \chemformula_prime: }
+          { \chemformula_superscript:n { \chemformula_prime: } }
+      }
   }
 
 % --------------------------------------------------------------------------
@@ -2147,7 +2386,7 @@
       }
     \bool_set_false:N \l__chemformula_is_arrow_bool
   }
-\cs_generate_variant:Nn \chemformula_input_arrow:n { o }
+\cs_generate_variant:Nn \chemformula_input_arrow:n { o,V }
 
 % --------------------------------------------------------------------------
 % input compound name
@@ -2221,6 +2460,7 @@
       { _ } { \sb }
     \tl_replace_all:Nnn \l__chemformula_tmpa_tl
       { chemformulaplaceholder } { \_ }
+    % TODO: waum ist das auskommentiert
     % \__chemformula_reset:NV \l__chemformula_tmpa_tl \l__chemformula_tmpa_tl
     \tl_put_right:NV \l__chemformula_input_tl \l__chemformula_tmpa_tl
   }
@@ -2499,7 +2739,12 @@
 
 \cs_new_protected:Npn \__chemformula_lewis_elspec_pair_dots:
   {
-    \chemformula_draw:nn { fill }
+    \chemformula_draw:nn
+      {
+        fill,
+        inner~sep=0pt,
+        outer~sep=0pt
+      }
       {
         (node~cs \c_chemformula_colon_tl
           name  = chlewis-\int_use:N \g__chemformula_lewis_int ,
@@ -2561,7 +2806,12 @@
 
 \cs_new_protected:Npn \__chemformula_lewis_elspec_single:
   {
-    \chemformula_draw:nn { fill }
+    \chemformula_draw:nn
+      {
+        fill,
+        inner~sep=0pt,
+        outer~sep=0pt
+      }
       {
         (node~cs \c_chemformula_colon_tl
           name  = chlewis-\int_use:N \g__chemformula_lewis_int ,
@@ -2777,10 +3027,21 @@ VERSION HISTORY
                           - new option stoich-print
                           - new command \chstoich
 2014/01/29 - version 4.4  - treat a single `-' as a minus sign
+2014/04/07 - version 4.5  - make sure that < and > have catcode 12 when read
+                            as parts of arrows
+                          - new arrow types `>=<', `>=<<', `>>=<' and `<==>'
+                          - arrow lengths and compound offset now correctly
+                            adapts to new fontsize if relative lengths (em,ex)
+                            are used
+                          - allow optional arguments to \\ in equation
+                            environments
+                          - allow optional arguments to \label in equation
+                            environments
+                            (credits: http://tex.stackexchange.com/a/166661/5049)
+                          - support for Kröger-Vink notation
 
 % --------------------------------------------------------------------------
 % TODO
 - Addukte: Zahlen nach * und . automatisch erkennen?
-- optionale Argumente von \\ nach außen
 - make escaped text/math /truely/ escaped, i.e., behave as if it's been input
   /outside/ of \ch
diff --git a/Master/texmf-dist/tex/latex/chemmacros/chemmacros.sty b/Master/texmf-dist/tex/latex/chemmacros/chemmacros.sty
index 5c95c03bf23..846a9d86fcd 100644
--- a/Master/texmf-dist/tex/latex/chemmacros/chemmacros.sty
+++ b/Master/texmf-dist/tex/latex/chemmacros/chemmacros.sty
@@ -26,8 +26,8 @@
 % - The Current Maintainer of this work is Clemens Niederberger.
 % --------------------------------------------------------------------------
 \RequirePackage{ expl3 , xparse , l3keys2e }
-\def\chemmacros@version{4.4}
-\def\chemmacros@date{2014/01/29}
+\def\chemmacros@version{4.5}
+\def\chemmacros@date{2014/04/08}
 
 \ProvidesExplPackage
   {chemmacros}
@@ -57,6 +57,7 @@
 \cs_generate_variant:Nn \tl_set_rescan:Nnn { NnV }
 \cs_generate_variant:Nn \tl_if_eq:nnTF     { V }
 \cs_generate_variant:Nn \tl_const:cn       { cV }
+\cs_generate_variant:Nn \tl_to_lowercase:n { f }
 
 % --------------------------------------------------------------------------
 % load required packages
@@ -1393,21 +1394,49 @@
 % --------------------------------------------------------------------------- %
 % acid / base
 \tl_new:N  \l__chemmacros_k_acid_tl
-\tl_set:Nn \l__chemmacros_k_acid_tl  { \chemmacros_translate:n { K-acid } }
 \tl_new:N  \l__chemmacros_k_base_tl
-\tl_set:Nn \l__chemmacros_k_base_tl  { \chemmacros_translate:n { K-base } }
 \tl_new:N  \l__chemmacros_k_water_tl
-\tl_set:Nn \l__chemmacros_k_water_tl { \chemmacros_translate:n { K-water } }
+
+\bool_new:N \l__chemmacros_subscript_lowercase_bool
+
+\tl_set:Nn \l__chemmacros_k_acid_tl
+  {
+    \bool_if:NTF \l__chemmacros_subscript_lowercase_bool
+      { \tl_to_lowercase:f }
+      { \use:n }
+    { \chemmacros_translate:n { K-acid } }
+  }
+
+\tl_set:Nn \l__chemmacros_k_base_tl
+  {
+    \bool_if:NTF \l__chemmacros_subscript_lowercase_bool
+      { \tl_to_lowercase:f }
+      { \use:n }
+    { \chemmacros_translate:n { K-base } }
+  }
+
+\tl_set:Nn \l__chemmacros_k_water_tl
+  {
+    \bool_if:NTF \l__chemmacros_subscript_lowercase_bool
+      { \tl_to_lowercase:f }
+      { \use:n }
+    { \chemmacros_translate:n { K-water } }
+  }
 
 \keys_define:nn { chemmacros / acid-base }
   {
-    p-style           .choice: ,
-    p-style / slanted .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textsl ,
-    p-style / italics .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textit ,
-    p-style / upright .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textup ,
-    K-acid            .tl_set:N = \l__chemmacros_k_acid_tl ,
-    K-base            .tl_set:N = \l__chemmacros_k_base_tl ,
-    K-water           .tl_set:N = \l__chemmacros_k_water_tl
+    p-style             .choice: ,
+    p-style / slanted   .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textsl ,
+    p-style / italics   .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textit ,
+    p-style / upright   .code:n   = \cs_set_eq:NN \chemmacros_p_style:n \textup ,
+    K-acid              .tl_set:N = \l__chemmacros_k_acid_tl ,
+    K-base              .tl_set:N = \l__chemmacros_k_base_tl ,
+    K-water             .tl_set:N = \l__chemmacros_k_water_tl ,
+    subscript           .choice: ,
+    subscript / lowercase .code:n =
+      \bool_set_true:N \l__chemmacros_subscript_lowercase_bool ,
+    subscript / uppercase .code:n =
+      \bool_set_false:N \l__chemmacros_subscript_lowercase_bool
   }
 
 \cs_new_eq:NN \chemmacros_p_style:n \textup
@@ -4015,10 +4044,15 @@
 % --------------------------------------------------------------------------
 % language support -- provided through `translations'
 % equilibrium constants:
-\DeclareTranslationFallback{K-acid}{A}
-\DeclareTranslationFallback{K-base}{B}
-\DeclareTranslationFallback{K-water}{W}
-\DeclareTranslation{German}{K-acid}{S}
+\DeclareTranslationFallback {K-acid}  {A}
+\DeclareTranslation{German} {K-acid}  {S}
+\DeclareTranslation{Dutch}  {K-acid}  {Z}
+
+\DeclareTranslationFallback {K-base}  {B}
+% \DeclareTranslation{Dutch} {K-base}  {B}
+
+\DeclareTranslationFallback {K-water} {W}
+% \DeclareTranslation{Dutch} {K-water} {W}
 % phases:
 \DeclareTranslation{German}{phase-sld}{ f }
 \DeclareTranslation{German}{phase-lqd}{ f{}l }
@@ -4028,12 +4062,14 @@
 \DeclareTranslation{German}  {list-of-reactions} { Reaktionsverzeichnis }
 \DeclareTranslation{Italian} {list-of-reactions} { Elenco~ delle~ reazioni }
 \DeclareTranslation{French}  {list-of-reactions} { Table~ des~ r\'eactions }
+\DeclareTranslation{Dutch}   {list-of-reactions} { Lijst~ van~ reacties }
 %
 \DeclareTranslationFallback  {reaction} { Reaction }
 \DeclareTranslation{English} {reaction} { Reaction }
 \DeclareTranslation{German}  {reaction} { Reaktion }
 \DeclareTranslation{Italian} {reaction} { Reazione }
 \DeclareTranslation{French}  {reaction} { R\'eaction }
+\DeclareTranslation{Dutch}   {reaction} { Reactie }
 
 \tl_set:Nn \l__chemmacros_reaction_lorname_tl
   { \chemmacros_translate:n {reaction} }
@@ -4291,6 +4327,8 @@ Version history
                             changes in `translations'
                           - new option `nmr/atom-number-cs'
                           - new option `nmr/coupling-pos-cs'
+2014/04/08 - version 4.5  - new option `acid-base/subscript'
+                          - added Dutch translations
 
 % --------------------------------------------------------------------------- %
 % TODO:
diff --git a/Master/texmf-dist/tex/latex/chemmacros/ghsystem.sty b/Master/texmf-dist/tex/latex/chemmacros/ghsystem.sty
index e65997437f2..ebe94bd0db3 100644
--- a/Master/texmf-dist/tex/latex/chemmacros/ghsystem.sty
+++ b/Master/texmf-dist/tex/latex/chemmacros/ghsystem.sty
@@ -27,8 +27,8 @@
 % - The Current Maintainer of this work is Clemens Niederberger.            - %
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \RequirePackage{ expl3, xparse, l3keys2e }
-\def\ghsystem@version{4.2e}
-\def\ghsystem@date{2014/01/09}
+\def\ghsystem@version{4.5}
+\def\ghsystem@date{2014/04/08}
 \ProvidesExplPackage
   {ghsystem}
   {\ghsystem@date}
@@ -641,7 +641,7 @@ VERSION HISTORY
                           - added \ghsystem_dash: and \ghsystem_slash:
 2014/01/09 - version 4.2e - bug fix: namespace after language file loading
                             properly restored
-2014/??/?? - version 4.3  - small changes in `ghsystem_italian.def'
+2014/04/08 - version 4.5  - small changes in `ghsystem_italian.def'
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % TODO: