摘要：

The results of a systematic study of molecular properties by density functional theory (DFT) are presented and discussed. Equilibrium geometries, dipole moments, harmonic vibrational frequencies, and atomization energies were calculated for a set of 32 small neutral molecules by six different local and gradient‐corrected DFT methods, and also by theabinitiomethods Hartree–Fock, second‐order Mo/ller–Plesset, and quadratic configuration interaction with single and double substitutions (QCISD). The standard 6‐31G* basis set was used for orbital expansion, and self‐consistent Kohn–Sham orbitals were obtained by all DFT methods, without employing any auxiliary fitting techniques. Comparison with experimental results shows the density functional geometries and dipole moments to be generally no better than or inferior to those predicted by the conventionalabinitiomethods with this particular basis set. The density functional vibrational frequencies compare favorably with theabinitioresults, while for atomization energies, two of the DFT methods give excellent agreement with experiment and are clearly superior to all other methods considered.

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