A linear text format which can describe the connectivity and chirality of a molecule
OpenBabel implements the OpenSMILES specification.
It also implements an extension to this specification for radicals.
| a | Output atomclass like [C:2], if available |
| c | Output in canonical form |
| h | Output explicit hydrogens as such |
| i | Do not include isotopic or chiral markings |
| n | No molecule name |
| r | Radicals lower case eg ethyl is Cc |
| t | Molecule name only |
| x | append X/Y coordinates in canonical-SMILES order |
| C | ‘anti-canonical’ random order (mostly for testing) |