title: Investigation of Exchange Energy Density Functional Accuracy for Interacting Molecules.
abstract: We present a comparison of exchange-only interaction energies obtained using several standard exchange functionals in the generalized gradient approximation to Hartree-Fock results for interacting molecules. We observe that functionals with an enhancement factor using a 2/5 power dependence on the gradient of the density for large density gradients offer consistently better agreement with Hartree-Fock calculations than that of alternative functionals. We revisit the functional offering the closest agreement and recalculate it to include its exact large gradient dependence.
authors.affiliation: Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, New Jersey 08854-8019.
authors.forename: Éamonn D
authors.initials: ÉD
authors.lastname: Murray
authors.affiliation: Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, New Jersey 08854-8019.
authors.forename: Kyuho
authors.initials: K
authors.lastname: Lee
authors.affiliation: Department of Physics and Astronomy, Rutgers University, 136 Frelinghuysen Road, Piscataway, New Jersey 08854-8019.
authors.forename: David C
authors.initials: DC
authors.lastname: Langreth