I want to write a reversible chemial reaction using
what I call double harpoons, but they don't seem to
exist in LaTeX. Or do they? Using \longdoublearrows
doesn't quite make it.

--
db

On 2024-09-06 09:28:22 +0000, db said:

> I want to write a reversible chemial reaction using
> what I call double harpoons, but they don't seem to
> exist in LaTeX. Or do they? Using \longdoublearrows
> doesn't quite make it.

I have felt the same need and the same frustration at not finding a
good solution.

What I do is

\newcommand {\reversible}{\hspace*{-0.08cm}\begin{array}{c}
_\rightarrow\\[-0.17cm]
^\leftarrow\\
\end{array}\hspace*{-0.08cm}}

This does what I want, but not necessarily what you want.

--
Athel -- French and British, living in Marseilles for 37 years; mainly
in England until 1987.

Am Fri, 6 Sep 2024 09:28:22 -0000 (UTC) schrieb db:

> I want to write a reversible chemial reaction using
> what I call double harpoons, but they don't seem to
> exist in LaTeX. Or do they? Using \longdoublearrows
> doesn't quite make it.

\documentclass{article}
\usepackage{chemformula}
\begin{document}
$\rightleftharpoons$

\ch{N<>N} \ch{N<=>N} \ch{N>=<N} \ch{N<=>>N}

\end{document}

--
Ulrike Fischer
http://www.troubleshooting-tex.de/

In article <vbehvm$p6bk$1@dont-email.me>, dieterhansbritz@gmail.com
says...
>
> I want to write a reversible chemial reaction using
> what I call double harpoons, but they don't seem to
> exist in LaTeX. Or do they? Using \longdoublearrows
> doesn't quite make it.

You can use the chemarrow package, it provides (amongst others) the
\rightleftharpoons and \autorightleftharpoons{}{} commands. In the
latter command, the length of the harpoons is adjusted to the text above
and below them.

--
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