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Semi-metallic Be5C2 monolayer global minimum with quasi-planar pentacoordinate carbons and negative Poisson's ratio.

ABSTRACT: Designing new materials with novel topological properties and reduced dimensionality is always desirable for material innovation. Here we report the design of a two-dimensional material, namely Be5C2 monolayer on the basis of density functional theory computations. In Be5C2 monolayer, each carbon atom binds with five beryllium atoms in almost the same plane, forming a quasi-planar pentacoordinate carbon moiety. Be5C2 monolayer appears to have good stability as revealed by its moderate cohesive energy, positive phonon modes and high melting point. It is the lowest-energy structure with the Be5C2 stoichiometry in two-dimensional space and therefore holds some promise to be realized experimentally. Be5C2 monolayer is a gapless semiconductor with a Dirac-like point in the band structure and also has an unusual negative Poisson's ratio. If synthesized, Be5C2 monolayer may find applications in electronics and mechanics.

SUBMITTER: Wang Y

PROVIDER: S-EPMC4857406 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Semi-metallic Be5C2 monolayer global minimum with quasi-planar pentacoordinate carbons and negative Poisson's ratio.

Wang Yu Y Li Feng F Li Yafei Y Chen Zhongfang Z

Nature communications 20160503

Designing new materials with novel topological properties and reduced dimensionality is always desirable for material innovation. Here we report the design of a two-dimensional material, namely Be5C2 monolayer on the basis of density functional theory computations. In Be5C2 monolayer, each carbon atom binds with five beryllium atoms in almost the same plane, forming a quasi-planar pentacoordinate carbon moiety. Be5C2 monolayer appears to have good stability as revealed by its moderate cohesive e ...[more]

PMID: 27139572

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