|a+||//*….*//||Comment||//* prod. by Jmol *//||Optional; application-dependent; no general function; removal does not affect processing|
|a+||<whitespace>||Allowed for formatting||Optional use of whitespace; removal does not affect processing of Jmol SMILES (however there may be aspects of Jmol SMARTS that require whitespace, these are application-dependent).|
|a+||/…../||Processing directive||/strict/c1cccccc1||Optional; if present, must precede molecule description; see discussion and Table 3|
|+||[Xx]||Dummy atom||[Xx]||The atomic symbol “Xx” represents a “dummy” atom that is present but not part of the actual chemical structure|
|+||<lower-case symbol>||Aromatic atoms||c1cocc1||
Any atom other than hydrogen may be indicated as aromatic. Note that only b, c, n, o, p, si, and se are allowed to be aromatic using the processing directives/open/or/strict/(see below).
|+||%(n)||Unlimited connectivity||C%(102)CCC%(102)||Any non-negative number|
|+||a=a||Aromatic double bond||c1cc(O)=c(O)cc1||A specific double bond Kekulization, but still aromatic|