OEGasteigerInitialCharges¶
bool OEGasteigerInitialCharges(OEMolBase &mol)
Calculates the seed charge partial charges used by the Marsilli-Gasteiger partial charge algorithm.
Gasteiger initial charges assign the partial charge of -0.5
to
atoms of type OETriposType_Oco2
, i.e.
carboxylate oxygens, and use the formal charge as the partial charge
on all other atoms except those in conjugated rings. For conjugated
ring systems, consisting of Tripos atom types
OETriposType_C2
,
OETriposType_Car
,
OETriposType_N2
,
OETriposType_Nar
,
OETriposType_Npl3
and
OETriposType_Nam
, the sum of the formal charges of
the atoms in the ring system are divided equally amongst all atoms in
the ring system. For example, the five heavy atoms in imidazolium
([nH+]1c[nH]cc1
), each get a partial charge of 0.2
. O
Warning
It is not necessary to call OEGasteigerInitialCharges
function prior to calling OEGasteigerPartialCharges
function.
See also
OETriposAtomTypes
to determine Tripos atom types