DENSITY-FUNCTIONAL THEORY PREDICTIONS OF THE NONLINEAR-OPTICAL PROPERTIES OF MOLECULES

First- (beta) and second-order (gamma) hyperpolarizabilities of substituted benzenes have been calculated by applying density functional (DFT) theory at the local (LDFT) and nonlocal (NLDFT) levels with field induced polarization (FIP) functions augmenting the basis sets. At the LDFT level without FIP functions, beta and gamma are predicted to be too small as compared to experiment, whereas inclusion of FIP functions at the LDFT or NLDFT level leads to an increase in beta and gamma giving good agreement with experiment. The inclusion of nonlocal corrections improves the agreement of the calculated beta and gamma values with experiment although the improvement is not large. Based on a comparison with ab initio molecular orbital theory values, calculations at the NLDFT/FIP level yield values which are comparable to those at the MP-2 level. DFT calculations on the nonlinear optical properties of indoaniline and porphines are also presented.