New implementation of molecular double point-group symmetry in four-component relativistic Gaussian-type spinors

摘要

A new, practical implementation of double-group symmetry to relativistic Gaussian spinors is presented for four-component relativistic molecular calculations. We show that the systematic adaptability to irreducible representations under arbitrary point-group symmetry, as well as Kramers (time-reversal) symmetry, is inherent in the present basis spinors, which possess the analytic structure of Dirac atomic spinors. The implementation of double-group symmetry entails significant computational efficiencies in the relativistic second-order Moller-Plesset perturbation calculation on Au-2 and the density functional theory (DFT) calculation with the B3LYP functional on octahedral UF6, in which the highest symmetries used are, respectively, C-6h* and D-4h*. The four-component B3LYP equilibrium geometry of UF6 is reported. (C) 2006 Wiley Periodicals, Inc.