Abstract

The dipole moment mu and the electronic (hyper)polarizabilities alpha, beta, and gamma tensors of paranitroaniline (PNA) has been calculated in the static regime with the B3LYP hybrid approach of the density functional theory (DFT) formalism and by using the numerical triple finite field method of Kamada et at. The calculations were performed with planar C-2v optimized geometry and the standard 6-31+G(d,p), d optimized 6-31+G(d*,p) and the specialized Sadlej basis sets. The B3LYP/6-31+G(d*,P) results of mu, a, beta, and gamma are comparable to those of the literature. In particular, the static average gamma of PNA is comparable to MP2 calculations and is able to reproduce 54% of the experimental static value from Z-scan experiments recently reported. The origin of the differences between the experimental and theoretical values is discussed. The findings emphasize the use of the DFT methodology in conjunction with optimized basis sets for a reasonable estimated of the electron correlation in static second hyperpolarizability calculations of push-pull conjugated molecules.