added groups to nomenclature

main.tex

@@ -26,6 +26,7 @@
 \usepackage{tikz}                   % painting
 \usepackage{tikz-imagelabels}       % overlay labels for images
 \usepackage{cite}                   % citation for bibliography
+\usepackage{amssymb}                % provides enhancements for mathematical formulas
 
 \makeindex
 \makenomenclature

nomencl.tex

@@ -1 +1,16 @@
-\nomenclature{\(c\)}{Speed of light in a vacuum}
+% For more verbose examples see: https://www.overleaf.com/learn/latex/Nomenclatures
+
+% Create groups for different nomenclature sections
+\renewcommand\nomgroup[1]{%
+  \item[\bfseries
+  \ifstrequal{#1}{P}{Physikalische Konstanten}{
+  \ifstrequal{#1}{E}{Chemische Elemente}{
+  \ifstrequal{#1}{Z}{Zahlenreihen}{
+  \ifstrequal{#1}{O}{Andere Symbole}}}}
+]}
+
+% Quick examples:
+% \nomenclature[P]{\(c\)}{Speed of light in a vacuum}
+% \nomenclature[Z]{\(\mathbb{C}\)}{Complex numbers}
+%              ^^^    ^^^^^^^^^^   ^^^^^^^^^^^^^^^
+%            Gruppe  Darstellung    Beschreibung