Zhi-Xin Hu (胡智鑫)1, Wei Ji (季威)1,*, and Hong Guo (郭鸿)2
1Department of Physics, Renmin University of China, Beijing 100872, China
2Centre for the Physics of Materials and Department of Physics, McGill University, Montreal, Quebec, Canada H3A 2T8
DOI:10.1103/PhysRevB.84.085414 Publication Date: 23 August 2011
Glycine molecules deposited on a Cu(100) surface give rise to an anisotropic free-electron-like (FEL) electronic dispersion in its p(2×4) superstructure, as reported in recent experiments [ K. Kanazawa et al.Phys. Rev. Lett. 99 216102 (2007); J. Am. Chem. Soc. 129 740 (2007)]. Using density functional theory and exhaustively calculating sixteen possible structures, we have determined the molecular arrangement that can give the experimentally observed FEL behavior. Eight configurations, among the sixteen, were not investigated before in the literature and one of them (denoted Str-3) is able to provide the FEL behavior in excellent agreement with the experiments. In addition, the particular configuration Str-3 satisfies other criteria of the observed p(2×4) superstructure, e.g., chirality and cleavable orientation.