I'm trying to get this kind of appearance for chemical structure (see highlighted regions):

By so far I could manage to do like this:

This is my code:
\documentclass[12pt]{standalone}
\usepackage{tikz}
\usepackage{fontspec}
\setmainfont{Times New Roman}
\usepackage{chemfig}
\usepackage[version=3]{mhchem}
\usetikzlibrary{arrows,shadows,calc,shapes,backgrounds,intersections,positioning}
\makeatletter
\def\CF@node@content{%
\expandafter\expandafter\expandafter
\printatom\expandafter\expandafter\expandafter
{\csname atom@\number\CF@cnt@atomnumber\endcsname}%
\ensuremath{\CF@node@strut}%
}
\makeatother
\setdoublesep{0.35700 em} % 'Bond Spacing'
\setatomsep{1.78500 em} % 'Fixed Length'
\setbondoffset{0.18265 em} % 'Margin Width'
\newcommand{\bondwidth}{0.06642 em} % 'Line Width'
\setbondstyle{line width = \bondwidth}
\renewcommand*{\printatom}[1]{{\sffamily\cf{#1}}}
\begin{document}
\begin{tikzpicture}[font=\small ,line width=1pt,node distance=1cm, inner sep=-0.05cm]
\node[anchor=north] at(0,0){
\chemname{
\chemfig{[:135]Ru?[o](-[,2.2]N*6([:80]=-=-*6(=<=>(-*6([:-120]-=(-*6(-=-(-*6(=*6(-=-=-)-=-*6(-=-=-)=-))=-=-))-=([:-80]-*6(=-=-*6(-=-[,,,,line width=2pt]=N?[o,{-}]-)=-))-N?[o,{-}]=))=)--))([:45]-[,2.2]N*6([:100]-*6(-(-*6([:-60]-N?[o,{-}]=([:-100]-*6(=*6(-N?[o,{-}]=-=-)-=<=>-))-=(-*6(=-=(-*6(-*6(-=-=-)=-=*6(-=-=-)-=))-=-))-=))=-@{tr}=-=)--=-[,,,,line width=2pt]=))}}{\textbf{\large 2}}
\chemmove{\draw[very thick,inner sep=0pt](tr)++(1cm,-.1cm)--++(0,2em)node[anchor=north west,yshift=-4mm]{$\sf \left(PF_{6}\right)_2$}--++(-2em,0);}
};
\path (0,.5)--++(2,0);
\path (0,-6.5)--++(1,0);
\end{tikzpicture}
\end{document}
How I could achieve the appearance I want using chemfig?


chemfigmanual has an example) – cgnieder Oct 19 '14 at 13:02