# Drawing a chemical molecule structure

Being a mechanical engineer I never had the necessity to draw chemical formulas/molecule structures in LaTeX, but now I have to draw the structure of Polyethylene glycol. So I was looking at examples of how to use chemfig and doing the chain was pretty basic, but I have no idea how to put the parentheses around the bit to be repeated n times. Could someone please help me out? Thanks!

MWE

\documentclass{scrreprt}
\usepackage{chemfig}
\begin{document}
\chemfig{H-[:30]O-[:-30]-[:30]-[:-30]O-[:30]H}
\end{document}


I got:

I need:

A starting point borrowed from the manual chemfig manual page number: 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}


you will get:

Disclaimer: I am not sure about the technical accuracy. Because, I am not a chemist :).

• That should do it: I can tweak the position of the parentheses with the parameters I think. Thanks! – Superuser27 Mar 12 at 15:18
• @Superuser27 you are welcome. – Raaja Mar 12 at 16:05