title: Identification of the au coverage and structure of the Au/Si(111)-(5 × 2) surface.
abstract: We identify the atomic structure of the Au/Si(111)-(5 × 2) surface by using density functional theory calculations. With seven Au atoms per unit cell, our model forms a bona fide (5 × 2) atomic structure, which is energetically favored over the leading model of Erwin et al. [Phys. Rev. B 80, 155409 (2009)], and well reproduces the Y-shaped and V-shaped (5 × 2) STM images. This surface is metallic with a prominent half filled band of surface states, mostly localized around the Au-chain area. The correct identification of the atomic and band structure of the clean surface further clarifies the adsorption structure of Si adatoms and the physical origin of the intriguing metal-to-insulator transition driven by Si adatoms.
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Se Gab
authors.initials: SG
authors.lastname: Kwon
authors.affiliation: Department of Physics, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Myung Ho
authors.initials: MH
authors.lastname: Kang