Sebastian Kozuch and Jan M. L. Martin
An extensive search for the most accurate, dispersion-corrected, spin-component-scaled, double hybrid (DSD) density functional theory functionals is reported. Performance only mildly depends on the choice of underlying generalized gradient approximations exchange and correlation functionals; even DSD-LDA performs respectably. Only a handful of empirical parameters are involved. Our best choices, DSD-PBEP86 and DSD-PBEhB95, achieve accuracy comparable to composite ab initio methods for a wide variety of thermochemical, kinetic, and spectroscopic properties.