LaTeX Forum

\usepackage[
    per-mode = reciprocal, 
    locale=DE% output-decimal-marker={,}, exponent-product = {\cdot}
]{siunitx}

\documentclass[a4paper,10pt, enabledeprecatedfontcommands]{scrreprt}
\usepackage[left=3cm,right=2cm,top=2cm,bottom=2cm,includehead]{geometry}
\usepackage[parfill]{parskip}
\usepackage[onehalfspacing]{setspace}
\usepackage[T1]{fontenc}
\usepackage[ngerman]{babel}
\usepackage[utf8]{inputenc}
\usepackage{amsmath}
\usepackage{graphicx}
\usepackage{tabularx}
\usepackage{booktabs}
\usepackage{here}
\usepackage[per-mode = reciprocal, output-decimal-marker={,}, exponent-product = {\cdot}]{siunitx}
\usepackage[version=3]{mhchem}
\usepackage{pdfpages} 

\begin{table}[htbp]
  \centering
  \caption{Add caption}
    \begin{tabular}{cc}
    \textbf{\$\textbackslash{}frac{\textbackslash{}vartheta }{ \textbackslash{}circ C}\$} & \textbf{\$\textbackslash{}frac{\textbackslash{}vartheta\$}{ \textbackslash{}circ C}} \\
    356   & 2 \\
    379   & 2 \\
    399   & 4 \\
    418   & 4 \\
    438   & 6 \\
    456   & 6 \\
    \end{tabular}%
  \label{tab:addlabel}%
\end{table}%]