Evaluation an dcomparison of transition states with the HCTH98 and FT97 functionals

摘要

A series of seven transition states was examined using the new pure densityfunctionals,Hamprecht-Cohen-Tozer-Handy 1998(HCTH98) and Filatov-Thiel 1997 (FT97).Both HCTH98 surpass older pure functionals in quality and compare favorably to hybrid functionals,exhibiting good geometries and frequencies.HCTH98 outpuerforms all of the pure and hybrid functionals regarding barrier-height calculations,whereasFT97 rivals hybrids in accuracy.Basis-set effects ranging from 6-31 G(d) to aug-cc-p VTZ were investigated and determined to be minimal.The use of fitting basis sets to obtain third-order scaling had negligible effects.