Kohn—Sham bond lengths and frequencies calculated with accurate quadrature and large basis sets

✍ Scribed by Christopher W. Murray; Gregory J. Laming; Nicholas C. Handy; Roger D. Amos

• Book ID: 103034616
• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 541 KB
• Volume: 199
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(92)85008-x

✦ Synopsis

We report calculations of bond lengths and frequencies using Kobn-Sham theory, defmed as replacir~g the exchange term in the I%tree-Fock self-consistent field procedure by potentials of density functional theory. Several fimctionals are tested including the local density approximation to tbe exchange energy, Becke's non-local correction to the exchange, the Vosko-Wilk-Nusair functional for correlation with Perdew's non-local correction to the correlation energy and the Lee-Yane-Parr correlation fun& tional. High accuracy quadraWe is used, which enables the Sradient of the energy to lx calculated straightforwardly. The results are compared to Hnrtree-Fock theory and to hybrid Dm methods based on the Hartree-Fock density. On average, bond lengths from the hybrid method are much bttter than SCF bond lengths, and often better than those from second-order I&ller-Plesset theory. The Kohn-Sham bond lengths are rather long, but improve ss the basis set is increased, and for large basis sets bond lengths, dipole moments and frequencies appear on to be a signiticant improvement over SCF theory.