SEMIEMPIRICAL MOLECULAR-ORBITAL CALCULATION ON AMINOBENZIMIDAZOLES

Semiempirical SCF-MO methods like Pariser-Parr-Pople and CNDO/S have b een employed to calculate the excited singlet state charge densities, dipole moments and transition energies in aminobenzimidazoles. The cal culated transition frequencies match with the experimental values reas onably well. Predictions made regarding the change in acidity or basic ity of the nitrogen centres, have been correlated with experimental ob servations. The change in dipole moment upon excitation shows a mixed trend.