Basic chemical formulas like H₂SO₄ or [ClO₂]⁺ can be written in plain Unicode text. At some point the line between basic and non-basic has to be drawn, just as with arbitrarily stacked superscripts in math, and some sort of fancy-text solution has to take over.
UTC determined many years ago in response to a proposal, that alpha, beta and gamma, common in organic chemistry, were not acceptable for encoding as super/subscripts.
At the time, this was requested to support
plain text databases used for regulatory purposes, where these
were required as super or subscripts.
Later, the beta and gamma were encoded for phonetic notation, but not the alpha.
As a result, you can write basic formulas for select compounds, but not all. Given that these basic formulae don't need full 2-D layout, this still seems like an arbitrary restriction.
A./
This archive was generated by hypermail 2.2.0 : Mon Oct 03 2016 - 15:47:45 CDT