title: Interface energetics and level alignment at covalent metal-molecule junctions: pi-conjugated thiols on gold.
abstract: The energetics at the interfaces between metal and monolayers of covalently bound organic molecules is studied theoretically. Despite the molecules under consideration displaying very different frontier orbital energies, the highest occupied molecular levels are found to be pinned at a constant energy offset with respect to the metal Fermi level. In contrast, the molecular properties strongly impact the metal work function. These interfacial phenomena are rationalized in terms of charge fluctuations and electrostatics at the atomic length scale as determined by first-principles calculations.
authors.affiliation: School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, 30332-0400, USA.
authors.forename: Georg
authors.initials: G
authors.lastname: Heimel
authors.forename: Lorenz
authors.initials: L
authors.lastname: Romaner
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Brédas
authors.forename: Egbert
authors.initials: E
authors.lastname: Zojer