title: From Silicene to Half-Silicane by Hydrogenation.
abstract: Graphane is graphene fully hydrogenated from both sides, forming a 1×1 structure, where all C atoms are in sp(3) configuration. In silicene, the Si atoms are in a mixed sp(2)/sp(3) configuration; it is therefore natural to imagine a silicane structure analogous to graphane. However, a monatomic silicene sheet grown on substrates generally reconstructs into different phases, and only partially hydrogenated silicene with reconstructions had been reported before. In this work, we produce half-silicane, where one Si sublattice is fully H-saturated and the other sublattice is intact, forming a perfect 1×1 structure. By hydrogenating various silicene phases on a Ag(111) substrate, we found that only the (2√3×2√3)R30° phase can produce half-silicane. Interestingly, this phase was previously considered to be a highly defective or incomplete silicene structure. Our results indicate that the structure of the (2√3×2√3)R30° phase involves a complete silicene-1×1 lattice instead of defective fragments, and the formation mechanism of half-silicane was discussed with the help of first-principles calculations.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Jinglan
authors.initials: J
authors.lastname: Qiu
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Huixia
authors.initials: H
authors.lastname: Fu
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.|Department of Physics, Yunnan University , Kunming 650091, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Department of Physics, Yunnan University , Kunming 650091, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Meng
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Chen
authors.affiliation: Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.|Collaborative Innovation Center of Quantum Matter , Beijing 100871, China.
authors.forename: Kehui
authors.initials: K
authors.lastname: Wu
keywords: hydrogenation; scanning tunneling microscopy; silicane; silicene