title: FeB6 Monolayers: The Graphene-like Material with Hypercoordinate Transition Metal.
abstract: By means of density functional theory (DFT) computations and global minimum search using particle-swarm optimization (PSO) method, we predicted three FeB6 monolayers, namely α-FeB6, β-FeB6 and γ-FeB6, which consist of the Fe©Bx (x = 6, 8) wheels with planar hypercoordinate Fe atoms locating at the center of six- or eight-membered boron rings. In particular, the α-FeB6 sheet constructed by Fe©B8 motifs is the global minimum due to completely shared and well delocalized electrons. The two-dimensional (2D) boron networks are dramatically stabilized by the electron transfer from Fe atoms, and the FeB6 monolayers have pronounced stabilities. The α-FeB6 monolayer is metallic, while the β-FeB6 and γ-FeB6 sheets are semiconductors with indirect band gaps and significant visible-light absorptions. Besides the novel chemical bonding, the high feasibility for experimental realization, and unique electronic and optical properties, render them very welcome new members to the graphene-like materials family.
authors.affiliation: Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus , San Juan, Puerto Rico 00931, United States.
authors.forename: Haijun
authors.initials: H
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Materials Science, Jiangsu Key Laboratory of Biofunctional Materials, Nanjing Normal University , Nanjing, Jiangsu 210046, China.
authors.forename: Yafei
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus , San Juan, Puerto Rico 00931, United States.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Hou
authors.affiliation: Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus , San Juan, Puerto Rico 00931, United States.
authors.forename: Kaixiong
authors.initials: K
authors.lastname: Tu
authors.affiliation: Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus , San Juan, Puerto Rico 00931, United States.
authors.forename: Zhongfang
authors.initials: Z
authors.lastname: Chen