Density-functional calculations of molecular electron affinities

Electron affinities of twelve small molecules were calculated by density fu nctional theory using two different functionals(B88-P86 and B3LYP) combined with three different basis sets 6-31++G**:; 6-311++G**; aug-cc-pVTZ. Outer valence Green's function method is also employed for calculation of electr on affinities of the molecules. The two most efficient approaches were foun d to be the combination of (1)B88-P86 with 6-31++G**;: basis set and (2)B3L YP with 6-31++G**:;: The two approaches were employed to calculate electron affinities of some medium size molecules.