An investigation of the performance of a hybrid of Hartree-Fock and density functional theory

We explore a hybrid methodology in which the Hartree-Fock energy and density are combined with the nonlocal exchange functional of Becke (1988) and the nonlocal correlation functional of Lee, Yang and Parr (1988) to yield an estimate of the Schrödinger total energy. The resulting mean absolute deviation from a large number of experimental atomization energies, ionization potentials, electron affinities, and proton affinities is 3.86 kcal/mol. Performance comparisons are made with the recently developed G2 theory and nonconventional interpretations of the density functionals are discussed. © 1992 John Wiley & Sons, Inc.