Unable to change font using LuaLaTeX with usage of chemnum package

Question

I can't seem to change the font in LuaLaTeX using chemnum as a package. I would like to use Calibri (not Times New Roman) as the case is now. Here is my code:

\documentclass[12pt]{report}
\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm]{geometry}
\usepackage{fancyhdr} 
\usepackage{achemso} 
\usepackage{chemnum}
\usepackage{psfrag} 
\usepackage[crop=off]{auto-pst-pdf}
\usepackage{graphicx} 
\usepackage{wrapfig} 

\linespread{1.3}%1.5 line spacing

\begin{document}
\tableofcontents

\chapter{This is your chapter title}

\section{This is your section title}

\subsection{Here is an example}

\begin{wrapfigure}{l}{0.35\textwidth}
\vspace{-20pt} % removes 'white-space'
\begin{center}
\cmpdref{benzene} % replaces TMP1
\includegraphics{images/benzene.eps}
\end{center}
\vspace{-20pt}
\end{wrapfigure}

Add any text here and use \refcmpd{benzene} to refer to the compound. This way if you add a new figure in front of this one the numbering will automatically be changed. \\
Not totally sure if .eps is require or if only benzene would be sufficient.\\

Note: you need lualatex --shell-escape  -synctex=1 -interaction=nonstopmode %.tex in the configure texmaker for the lualatex. 

\end{document}

Answer 1

You have to load package fontspec and to define the main font:

\documentclass[12pt]{report}
\usepackage{achemso} 
\usepackage{chemnum}
\usepackage{fontspec}
\setmainfont{Calibri}
\begin{document}

Add any text here and use to refer to the compound. This way if you add a new figure 
in front of this one the numbering will automatically be changed. 

Not totally sure if .eps is require or if only benzene would be sufficient.
\end{document}

Answer 2

Herbet's answer is correct if you want to change the default font for the whole document. However, if it is just the labels produced by chemnum that you want to change then load fontspec and define a font for use and place its name in the format for the compound labels as follows:

\usepackage{fontspec}

\newfontface\chemnumface[Scale=MatchUppercase]{Calibri}
\setchemnum{format=\chemnumface}

However you also need this to work with psfrag and auto-pst-pdf. This requires some care switiching in and out of packages: the main file is run with lualatex which supports fontspec but the auto-pst-pdf runs with just latex which does not. You should load in the following order with ifluatex tests:

\usepackage{ifluatex}
\ifluatex
 \usepackage{fontspec}
  \newfontface\chemnumface[Scale=MatchUppercase]{Calibri}
  \setchemnum{format=\chemnumface}
\else
  \usepackage{psfrag} 
\fi
\usepackage[crop=off]{auto-pst-pdf}

\documentclass[12pt]{report}

\usepackage[a4paper,width=150mm,top=25mm,bottom=25mm]{geometry}
\usepackage{fancyhdr} 
\usepackage{achemso} 
\usepackage{chemnum}
\usepackage{ifluatex}
\ifluatex
 \usepackage{fontspec}
  \newfontface\chemnumface[Scale=MatchUppercase]{Calibri}
  \setchemnum{format=\chemnumface}
\else
  \usepackage{psfrag} 
\fi
\usepackage[crop=off]{auto-pst-pdf}
\usepackage{graphicx} 
\usepackage{wrapfig} 


\linespread{1.3}%1.5 line spacing

\begin{document}

\begin{wrapfigure}{l}{0.35\textwidth}
\centering
\replacecmpd{benzene} % replaces TMP1
%\includegraphics{benzene.eps}
\end{wrapfigure}

Add any text here and use \refcmpd{benzene} to refer to the
compound. This way if you add a new figure in front of this one the
numbering will automatically be changed. Here is another compound
\cmpd{xx.one}

\end{document}

I don't have your benzene.eps file so have commented out that line.