Change arrow head of \xrightarrow[]{}

Question

I am using \xrightarrow{} in many places in my document. I want to change the tip to look like the one that gets produced by -latex.

I am trying to get a similar tip for the \xrightarrow{} macro.

Answer 1

The chemarrow package provides extensible arrows with such heads, for example

\autorightarrow{above}{below}

amsmath uses \rightarrow for the extensible right arrow. You could easily use \chemarrow instead, changing also the fixed arrow for consistency:

\usepackage{chemarrow}
\let\rightarrow\chemarrow
...
$\xrightarrow{n\rightarrow\infty}$

Or patch just the amsmath extensible arrow command(s), keeping the original \rightarrow:

\makeatletter
\renewcommand*{\rightarrowfill@}{%
  \arrowfill@\relbar\relbar\chemarrow}
\makeatother