LCAO-MO-SCF-CI SEMI-EMPIRICAL PI-ELECTRON CALCULATIONS ON HETEROAROMATIC SYSTEMS .2. AMINO AROMATIC COMPOUNDS

The electronic spectra and structures of aromatic monoamino and diamino compounds have been calculated using a modification of the Pariser-Parr-Pople method. Electronic transitions investigated involve singlet-singlet and triplet-triplet π-π* excitations. A limited configuration interaction has been included involving single electron excitations and both single and double electron excitations between the two highest occupied and two lowest unoccupied molecular orbitals. Improvement of oscillator strengths was observed with increasing number of configurations considered. Good agreement was obtained between calculated and experimental molecular ionization potentials. © 1968 Springer-Verlag.