Solvent effect on static vibrational and electronic contribution of first-order hyperpolarizability of π-conjugated push-pull molecules:: quantum-chemical calculations

Results of ab initio quantum-chemical calculations of the first-order static electronic (beta (e)) and vibrational (beta (v)) hyperpolarizabilities for the prototype push-pull conjugated molecules 4-nitro-aniline, 4-nitro-4'-aminostilbene, 4-amino-4'-nitrobiphenyl, and 4-amino-4'-nitrodiphenylacetylene in the gas phase and in chloroform and aqueous solvents are presented. The coupled perturbed Hartree-Fock method and the sum-over-modes formalism was used to calculate individual components of beta (c) and beta (v) tensors. The solvent effect has been included via the continuum self-consistent reaction field model. The calculations demonstrate the existence of larger solvent effect on the beta (v) compared with beta (e) for molecules investigated in this paper. (C) 2000 Elsevier Science B.V. All rights reserved.