# Vertical positioning of superscripts with different heights

I'm trying to format some Clebsch-Gordan coefficients to look like this

i.e. a normal C followed by a 2x3 array (using super/subscripts; not an actual LaTeX array) of indices. But instead of j_1, j_2, my indices have Greek subscripts such as l_\alpha, which is fine until I have l_\beta and it throws the alignment out as such:

\documentclass{book}
\begin{document}
$C{}^{\,\,l_\beta}_{m_\beta}{}^2_0{}^{\,\,l_\alpha}_{m_\alpha}$
\end{document}


Interestingly, this only happens if the superscript has a _\beta; if it's only in the subscript there's no problem. It seems the low-hanging "tail" of the beta is pushing the whole superscript up and taking the subscript with it.

\usepackage{subdepth} doesn't help. I thought \vphantom{_\beta} could push everything up but that doesn't work well either. Is there any way to adjust the height of superscripts based on its top rather than its bottom? Or manually fine-tune its vertical position?

You can use a \mathstrut:

\documentclass{book}
\begin{document}
$C{\mathstrut}^{\,\,l_\beta}_{m_\beta}{\mathstrut}^2_0{\mathstrut}^{\,\,l_\alpha}_{m_\alpha}$
\end{document}


Here is a proposition which may be fine tuned.

\documentclass{book}
\usepackage{amsmath}
\begin{document}
$C\!% \begin{smallmatrix} l_{\beta} & \!\!2 & \!\!l_{\alpha} \\ m_{\beta} & \!\!0 & \!\!m_{\alpha} \end{smallmatrix}$
\end{document}


• the subscript \!\!m_{\alpha} looks too close to the zero in the last example. perhaps one less \! in both sub- and superscript. – barbara beeton Nov 24 '14 at 14:11
• @barbarabeeton Yes, I just wanted to demonstrate. Adjusting those things are up to OP. – user11232 Nov 24 '14 at 14:13