Solvent Perturbation of the Electronic Intensity of Solvated Absorbing Molecules

In this paper, we present a general expression originating from quantum-mechanical perturbation treatment of electronic intensities and Hamiltonian operators for the system (HA and HB) of an absorber and a perturber respectively. The expression is related to the Longuet-Higgins’ definition of solute-solvent interaction and fitted into linear regression mode for the determination of transition polarizabilities of 9H-xanthene, 9H-xathone and 9H-xanthione. The result conforms to those earlier obtained when all possible interaction modes are considered.