Ab Initio HF and DFT Calculation of the Second Order NLO Response of Tetrathiafulvalene and 1,3-Dithiole Derivatives

摘要

The nonlinear optical properties of new tetrathiafulvalenes and 1,3-dithioles have been studied using first principle methods. The higher hyperpolarizabilities of the extended 1,3-dithioles compared to Tetrathiafulvalene analogs are explained on the basis of the less localized HOMO of the former giving rise to higher transition dipole moments and a more pronounced decrease of the HOMO-LUMO gap on chain extension.