Performance and basis set dependence of density functional theory dipole and quadrupole moments

A study is presented concerning the performance and basis set dependence of density functional methods in the calculation of dipole and quadrupole moments. A set of some small molecules was thereby used, together with seven commonly used exchange correlation functionals and Dunnings correlation consistent aug-cc-pVDZ, aug-cc-pVTZ, aug-cc-pVQZ and aug-cc-pV5Z basis sets. The results were compared with experiment and previously published values obtained with traditional ab initio molecular orbital methods. The best performance in the calculation of dipole and quadrupole moments is due to the hybrid functionals B3LYP and B3PW91. Moreover, the results seem to be essentially converged at the aug-cc-pVTZ level. Comparison of the LDA/aug-cc-pV5Z results with the numerical LDA results of Dickson and Becke, reveals that both sets of values are identical for most cases. (C) 2000 Elsevier Science B.V. All rights reserved.