Calculation of macroscopic linear and nonlinear optical susceptibilities for the naphthalene, anthracene and meta-nitroaniline crystals

The macroscopic first- to third-order susceptibilities of naphthalene, anth racene and meta-nitroaniline (mNA) are calculated using a rigorous local fi eld approach. Molecular (hyper)polarizabilities used as input are determine d by density functional theory calculations with specially designed basis s ets and for mNA also by MP2 calculations with the 6-31++G** basis set. In t he case of mNA, the permanent electric local field due to the surrounding d ipoles in the crystal is taken into account for the first- and second-order susceptibility by a self-consistent approach. The molecular dipole moment and first hyperpolarizability of mNA are drastically changed by the permane nt local field. In all cases the calculated first-order susceptibility comp ares very favorably with experimental data, if the molecular response is di stributed over all heavy atoms in the molecules. Similarly, the calculated second-order susceptibility for mNA is in good agreement with available exp erimental data, if the same distribution scheme is used and the permanent l ocal field is taken into account properly. This implies that accurate value s for the molecular second-order hyperpolarizability gamma have to be avail able. The anisotropic Lorentz field factor approximation yields results that are only slightly worse than the best ones of the rigorous local field theory f or the first-order susceptibilities, but fails for the second-order suscept ibility of mNA, due to its incapability to describe the large effect of the permanent local field on the first-order hyperpolarizability beta. (C) 200 0 Elsevier Science B,V, All rights reserved.