Nonlinear optical properties of organic molecules. Part 15. Calculation of the structure and hyperpolarisabilities of arylalkenes containing weak donors and acceptors

Abstract

The structure of a series of 4-methoxyphenylpolyenals and furylpolyenals have been calculated at the AM1 level. The hyperpolarisabilities of these systems calculated using a semi-empirical sum-overstates approach increase with increasing conjugation path length between the aromatic ring and the terminal aldehyde group. The initial members of the series in both cases are transparent, possess relatively large hyperpolarisabilities which are comparable to molecules containing strong donors and acceptors, and have potential application as materials for second harmonic generation.