# Kröger Vink notation

This question led to a new feature in a package:
chemformula

How to properly typeset Kröger Vink notation?

I can try something like \ce{V_O^{..}} (using mhchem) but the dots are not aligned well and too thin. I tried googling it and I can see people have done it but not how.

Edit to add MWE:

\documentclass{report}
\usepackage{mhchem}
\begin{document}
\ce{O_O^x + Zn_{Zn}^x <-> 1/2 O2 + Zn_$i$^. + e^{-1}}
\end{document}

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Welcome to TeX.SX! Please help us to help you and add a minimal working example (MWE) that illustrates your problem. It will be much easier for us to reproduce your situation and find out what the issue is when we see compilable code, starting with \documentclass{...} and ending with \end{document}. –  Christian Hupfer Mar 23 at 9:37

Update: with version 4.5 (2014/04/08) chemformula has a basic native support for Kröger-Vink notation. It must be enabled with the option kroeger-vink=true:

\documentclass{article}
\usepackage{chemformula}[2014/04/08]

\begin{document}

\setchemformula{kroeger-vink}

\ch{Al_{Al}^x}

\ch{Ni_{Cu}^x}

\ch{V_{Cl}^{*}}

\ch{Ca_i^{**}}

\ch{e'}

\ch{Cl_i'}

\ch{O_i''}

\ch{O_O^x + Zn_{Zn}^x <-> 1/2 O2 + Zn_i^. + e^{-1}}

\end{document}


I've never heard from the Kröger Vink notation before... but from what a quick web search shows me the following should be correct. I use chemformula (from the chemmacros bundle) because it let's you customize the size of the dots and the amount of horizontal shift of superscripts:

\documentclass{article}
\usepackage{chemformula}

\begin{document}

\setchemformula{
radical-radius = .3ex , % a larger radical' dot
charge-hshift  = 0pt    % don't shift superscripts to the right if subscripts
% are present
}

\ch{Al_{Al}^{$\times$}}

\ch{Ni_{Cu}^{$\times$}}

\ch{V_{Cl}^{.}}

\ch{Ca_i^{..}}

\ch{e^{$\prime$}}

\ch{Cl_i^{$\prime$}}

\ch{O_i^{$\prime\prime$}}

\ch{O_O^{$\times$} + Zn_{Zn}^{$\times$} <-> 1/2 O2 + Zn_i^. + e^{-1}}

\end{document}


A question related to the “dot” symbol is How to get the the dot symbol in Chemistry? which may give you some more hints

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Just a small comment, though wikipedia gives the subscript i for interstitial as roman, it is more often seen as italic. ETA: I just checked IUPAC guide for nomenclature of inorganic chemistry and they use roman. –  Henk Metselaar Mar 23 at 10:36
Then _{$i$} would do –  cgnieder Mar 23 at 10:38
@HenkMetselaar Roman does make more sense: italics usually denote variables –  cgnieder Mar 23 at 13:53

When sticking with mhchem, simply swap _ and ^.

\documentclass{article}
\usepackage{mhchem}
\begin{document}
\ce{V^{..}_O}

\ce{O^x_O + Zn^x_{Zn} <-> 1/2 O2 + Zn^._i + e^{-1}}
\end{document}
`

As for the size of the dots, they are still relatively thin with mhchem. If you have a collection of text books from different publishers and they all agree that these dots should be bigger, then contact the author and he surely will update the package.

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