IUPAC mapping
AsciiChem constructs are designed against the IUPAC Green Book (3rd ed.,
2007) and IUPAC Recommendations (Pure Appl. Chem. 90, 2018, 175–180).
Where AsciiChem’s spelling differs from mhchem, the Green Book is the
tiebreaker.
| Construct | AsciiChem | IUPAC reference |
|---|---|---|
| Element symbol | C, He | Green Book §2.10 |
| Isotope (prefix) | ^14C | Green Book §2.10 (isotope) |
| Charge | Ca^2+ | Green Book §2.10 (number-then-sign) |
| Oxidation state | Fe^(III) | Green Book §2.10 (Roman in parens) |
| Stoichiometric coefficient | 2H_2O | Green Book §2.10 (prefix) |
| Forward reaction | A -> B | Rec. 2018 §3 |
| Equilibrium | A <=>[Fe][T] B | Rec. 2018 §3 (conditions) |
| Subscript | H_2 | Green Book §2.10 |
Divergences from mhchem
Section titled “Divergences from mhchem”Where mhchem (LaTeX) and AsciiChem diverge, the rationale is recorded
in TODO 01.
| Construct | mhchem | AsciiChem | Why |
|---|---|---|---|
| Charge | \ce{Ca^{2+}} | Ca^2+ | Plain ASCII; braces optional |
| Reaction | \ce{A -> B} | A -> B | Same — direct lift |
| Adduct | \ce{A·B} | (deferred) | Needs design; v2 |
| Bond | (none in mhchem) | -, =, # | Lifted from chemfig |
Open questions
Section titled “Open questions”Some chemistry typography is not yet modelled. Tracked in TODO 13:
- Stereochemistry (R/S, E/Z) markers
- Wedge/hash bonds in linear notation
- Multi-center bonds
- Reaction cascades (chained arrows)