MOLECULAR DIPOLE-MOMENTS CALCULATED WITH DENSITY-FUNCTIONAL THEORY

Molecular dipole moments (MDM) of 32 molecules calculated with density functional (DFT) and Hartree-Fock (HF) methods are compared and analy zed. We found that calculations with DFT using a DZVPD (double-zeta pl us polarization in valence orbitals and diffuse d functions on heavy a toms) basis set currently provide the best theoretical values of the v acuum MDM closest to the experimental values and to available results from large CI calculations. MDM from DFT using DZVPD basis set (DFT/DZ VPD), DFT/DZVP2 and HF/6-31G calculations lead to mean unsigned error s of 0.06, 0.18 and 0.30 D, respectively, relative to the experimental values. A use of triple zeta basis sets did not lead to further impro vements in the computed MDM.