Molecular quadrupole moments, second moments, and diamagnetic susceptibilities evaluated using the generalized gradient approximation in the framework of Gaussian density functional method

A series of monoelectronic properties, i.e., molecular dipole and quadrupole moments, diamagnetic susceptibility and second moments of a number of organic and inorganic systems (CO2, OCS, CS2, C2H2, HCN, SO2, CH3CN, C2H6, C6H5F, C5H5N, C4H4N2, and C2H2N4) have been determined by using the linear combination of Gaussian-type orbitals-density functional method employing both local spin density (LSD) and nonlocal spin density (NLSD) approximations and triple zeta quality basis sets. The possible influence of an increase of radial grid points on the calculated properties has been also examined. Results show a general good agreement between all calculated monoelectronic properties and the available experimental counterparts even at local level and with a fine grid employing 32 radial grid points. In particular for the considered molecules the average error, at nonlocal level, with respect to the experiment is about 0.4x10(-26) e.s.u. cm(2) for quadrupole moments, 2.0x10(-16) cm(2) for [r(2)] and 5.6x10(-6) ergs/G(2) mol for diamagnetic susceptibility, that is in the range of the experimental error. (C) 1996 American Institute of Physics.