如何在 chemfig 中垂直对齐括号前的字母？

Question

我怎样才能将这个小字母 n 垂直居中在左括号前？我希望它不在顶部，而是在中间。提前致谢。

\documentclass{article}
\usepackage{chemfig}

\begin{document}




\schemestart
n
\chemleft[
\chemfig{M([6]-R^{+;-})}
\chemright]
\arrow{->[Polymerisation][]}[0,2]
\chemfig{-[@{upleft,0.5},1]M([6]-R^{+;-})-[@{upright,0.5},1]}
\polymerdelim[delimiters ={[]}, height = 10pt, depth = 40pt, indice = n]{upleft}{upright}
\schemestop
\end{document}

Answer 1

使用不可见的箭头 ( ) 将相对于箭头\arrow{0}[,0]垂直居中：n

\documentclass{article}
\usepackage{chemfig}

\begin{document}
\schemestart
n  \arrow{0}[,0]
\chemleft[
\chemfig{M([6]-R^{+;-})}
\chemright]
\arrow{->[Polymerisation][]}[0,2]
\chemfig{-[@{upleft,0.5},1]M([6]-R^{+;-})-[@{upright,0.5},1]}
\polymerdelim[delimiters ={[]}, height = 10pt, depth = 40pt, indice = n]{upleft}{upright}
\schemestop
\end{document}