I encountered a conflict between the siunitx and pdfx packages. I had a document working, but after I added the pdfx package I ended up with an
! LaTeX Error: Command \AA unavailable in encoding TU.
Minimal working example (test_angstrom.tex):
\documentclass{report}
\usepackage[a-2u]{pdfx} % Force required PDF/A-2u format
\usepackage{siunitx} % Numbers and quantities
\begin{document}
\SI{1}{\angstrom}
\end{document}
A file with metadata test_angstrom.xmpdata needs to exists. I compile the source with lualatex. When I remove the pdfx package everything works. Any idea how can I introduce the angstrom symbol to the pdfx package?
\AAis not encoding specific, which might account for this issue. You could try defining the character and using that instead, as shown in a related answer. – Coby Viner Jun 20 '18 at 21:53