I want to create a curved arrow over a letter as a symbol for the moment over the letter. Like in this picture:
I tried using \curvedarrowleft{C} but it didn't have that kind of functionality.
[Tex/LaTex] Momentsymbol over a letter
symbols
Related Solutions
Using TikZ you can define a command that will give you a stretchable symbol; you can do something like this:
\documentclass{book}
\usepackage{tikz}
\newcommand\myarrow[1][1]{%
\raisebox{-0.5cm}{\begin{tikzpicture}\draw (0,0) -- (#1,0); \draw[->] (#1,0) -- (#1,-0.5);\end{tikzpicture}}}
\begin{document}
\noindent\myarrow[6.4]
\begin{equation}
x^n + y^n = z^n.
\end{equation}
\noindent\myarrow[4.8]
\begin{equation}
a= b + c + d + e + f.
\end{equation}
\end{document}
\hbar is defined in the LaTeX kernel:
\newcommand{\hbar}{\mathchar'26\mkern-9mu h}
So
\newcommand{\kbar}{\mathchar'26\mkern-9mu k}
should do what you want (although it might need some customization if other fonts are used).
Best Answer
\curvedarrowleftis a typo, I believe; try\curvearrowleftinstead.