# Greek Omega (Ohm) in running text ACM Whitelist conform

I am trying to get a Greek omega letter as an Ohm sign in the running text for my paper. I found a solution using siunitx or textgreek here. Unfortunately, the packages are not on the whitelist of ACM that can be found here. Any suggestions on how to solve this problem?

• Use the \ohm command from siunitx if it is on the list. You'll get both an upright Ω and a correct spacing with the \SI command Jul 16, 2020 at 11:57
• As mentioned in my question the package is not on the list. Jul 16, 2020 at 11:58
• It has the old SIunits package, though... and that should offer an upright Ω somewhere. Jul 16, 2020 at 12:10
• If you are restricted on packages, can you use simply \ensuremath{\Omega}? Jul 16, 2020 at 12:15
• You'll probably want to do \newcommand{\ohm}{\ensuremath{\Omega}} to (a) reduce typing and (2) allow you to easily make any necessary adjustments to formatting later. Jul 16, 2020 at 14:18

You can do this without any packages at all, by taking the symbol from the (default) OT1 encoding.

\documentclass{article}
\usepackage[OT1,T1]{fontenc}
\usepackage{textcomp}       % Not needed since 2020
\usepackage[utf8]{inputenc} % Not needed since 2018

\providecommand\textOmega{{\fontencoding{OT1}\selectfont\symbol{"0A}}}
\DeclareUnicodeCharacter{2125}{\textOmega} % Ohm symbol

\begin{document}
550~µΩ--600~\textmu\textOmega
\end{document}


In math mode with amsmath, you’d wrap this in \textnormal. If you want the units to stay upright even when the text is italicized, add \upshape between \fontencoding and \selectfont.

• These are precisely the kinds of things I'm trying very hard to understand: picking one character from a font, the various encodings and what they actually mean, 8 bit, unicode, etc. Where are these things documented and explained? Jul 16, 2020 at 20:00
• @LaTeXereXeTaL The font tables are in the LaTeX Font Encoding Guide, and \DeclareUnicodeCharacter is defined by inputenc and documented there. Jul 16, 2020 at 20:14
• @LaTeXereXeTaL The reference to the text font commands is LaTeX2e Font Selection Jul 16, 2020 at 20:15
• @LaTeXereXeTaL But for a good user-friendly document, you might go to the `LaTeX Wikibook or Overleaf’s documentation. Jul 16, 2020 at 20:17
• Okay some of these I'd seen before, but the second one you link to looks to be what I'm looking for. Jul 16, 2020 at 20:20