Phosphine oxides as novel acceptor groups in molecules presenting non-linear optical properties

Abstract
In search for molecules possessing high hyperpolarizabilities, β, the diphenylphosphine oxide group is used as a novel acceptor. Three phosphorus model compounds were synthesized and their non-linear optical (NLO) properties investigated. The results obtained from EFISH measurements are complemented by semi-empirical calculations performed with the AM1 hamiltonian method taking account of the angle, θ, between the dipole moment, µ, and the vector part of the tensor, β. Their high non-linear efficiencies [βx(O)=38–63 × 10–30 esu] make these compounds interesting for their potential use as NLO materials.