# How to make an oplus in mhchem

I would like to have an oplus and an ominus in LaTeX.

\documentclass{article}
\usepackage{amsmath, amssymb}
\usepackage[version=4]{mhchem}

\begin{document}
\ce{A^\oplus + A^\ominus}
\end{document}

• \ce{A$\!^\oplus$ + A$\!^\ominus$} perhaps? The mhchem manual states that this is basically the way to escape to math – user31729 Sep 4 '15 at 9:26
• \ce{A^{$\oplus$} + A^{$\ominus$}}? – clemens Sep 4 '15 at 9:27
• Thx that is the answer :-) – Amelie B. Blackstone Sep 4 '15 at 9:43

\oplus and \ominus are math symbols and must be used in math mode. This is also true in mhchem's formulas.

\documentclass{article}
\usepackage[version=4]{mhchem}

\begin{document}

\ce{A+ + A-} \par
\ce{A^{$\oplus$} + A^{$\ominus$}}

\end{document}


• A sortcut is \ce{A^$\oplus$ + A^$\ominus$} – mhchem Feb 22 '17 at 11:47
• @mhchem that is no correct latex syntax (even if it works…). – clemens Feb 22 '17 at 11:52
• It is 100% correct mhchem syntax. mhchem != LaTeX. H2O+ and ^227_90Th+ aren't valid LaTeX syntax either. – mhchem Feb 22 '17 at 12:41