借用手冊的起始點chemfig
手冊頁碼:44。
\documentclass{scrreprt}
\usepackage{chemfig}
\begin{document}
\chemfig{H-[@{left,0.25}:30]O-[:-30]-[:30]-[@{right,0.25}:-30]O-[:30]H}
\polymerdelim[delimiters ={[]}, height = 20pt, depth = 10pt, indice = n]{left}{right}
\end{document}
你會得到:

免責聲明:我不確定技術準確性。因為,我不是化學家:)
。