Abstract: Finite Field/PM3 calculation of the heat of formation, dipole moments, polarizabilities, first order hyperpolarizabilities and second order hyperpolarizabilities of 4-trifluoromethyl stilbene derivatives suggest that these compounds are good candidates for SHG materials. The second-order optical nonlinearities and transparencies trand off,the relationshop between β and ΔE (LUMO HOMO) and μ are discussed.