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The parts of chemical notation that are not a reaction arrow: stereochemical descriptors, the projections that put three dimensions on a flat page, the notation of equilibrium and thermodynamic state, electrochemical cell diagrams, and the machine-readable identifiers by which a chemical record is actually indexed. What holds the group together is that almost every member asserts something a reader could take for a drawing convention and is not — a wavy bond stating that stereochemistry is deliberately unspecified, a double bar claiming a junction potential has been made negligible, a raised circle that fixes pressure and activity but says nothing about temperature. Several members exist to separate a pair that are routinely confused: partial charge from formal charge, D and L from (+) and (−), a racemate from a meso compound, SMILES from InChI.
A single wavy line, meaning the configuration is unspecified.
A lowercase delta with a raised plus or minus.
Small capital D or L before a name, from a sugar's Fischer projection.
A plus or minus in brackets before a compound's name.
The letters rac or a bracketed plus-minus sign.
The italic word meso before a compound's name.
A Greek alpha or beta — a small curved letter — before a sugar's name.
A cross of straight lines with the vertical bonds going back.
A flat ring drawn in perspective with substituents up or down.
A circle with three bonds from the centre and three from the rim.
A small circle, often struck through, raised after a quantity.
A Greek gamma, correcting concentration to effective concentration.
A capital K with a lowercase a subscript.
A lowercase p before a capital K with an a subscript.
A capital K with sp as a subscript.
A capital E with a nought superscript, in volts.
A single upright stroke, marking a phase boundary.
Two upright strokes, marking a junction whose potential is negligible.
The letters aq in brackets after a formula.
A dagger with two crossbars, raised after a quantity.
A superscript, a capital letter and a subscript together.
A numeral, a lowercase letter and a raised count, repeated.
A Greek eta with a raised numeral, before a ligand's name.
A Greek kappa with a raised numeral, before a ligand's name.
A Greek mu with a raised numeral, before a ligand's name.
A single line of letters, digits and brackets encoding a structure.
A structured string beginning InChI= with slash-separated layers.
Digits in three hyphen-separated groups, the last a single check digit.
A capital H followed by three digits.
A capital P followed by three digits.
Four digits, often on an orange plate.
Carbon first, hydrogen second, then everything alphabetically.
A raised mass number before an element symbol in a formula.