title: Towards an accurate description of the electronic properties of the biphenylthiol/gold interface: the role of exact exchange.
abstract: We investigate the role of the exact exchange in describing the biphenylthiol/gold interface. The study is performed by simulating the electronic properties of mercaptobiphenylthiol and aminobiphenylthiol molecules adsorbed on a Au(23) cluster, using local, semilocal and hybrid functionals and an effective exact exchange method, namely, the localized Hartree-Fock (LHF). We find that the local/semilocal functionals strongly underestimate the charge transfer and the bond dipole at the interface due to the self-interaction-error (SIE), which alters the correct level alignment. On the other hand the LHF method is SIE free and predicts a larger charge transfer and bond dipole. We also found that LHF results can be reproduced using hybrid functionals and that conventional local/semilocal correlation functionals are unable to improve over the exchange-only description.
authors.affiliation: National Nanotechnology Laboratory of CNR-INFM, IIT Research Unit, Distretto Tecnologico ISUFI, Via per Arnesano, I-73100 Lecce, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Fabiano
authors.forename: M
authors.initials: M
authors.lastname: Piacenza
authors.forename: S
authors.initials: S
authors.lastname: D'Agostino
authors.forename: F
authors.initials: F
authors.lastname: Della Sala