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arXiv · 1711.09847

Dirac cones in Two-dimensional Borane

Miguel Martinez-Canales·Timur R. Galeev·Alexander I. Boldyrev·Chris J. Pickard
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Abstract

We introduce two-dimensional borane, a single-layered material of BH stoichiometry, with promising electronic properties. We show that, according to Density Functional Theory calculations, two-dimensional borane is semimetallic, with two symmetry-related Dirac cones meeting right at the Fermi energy $E_f$. The curvature of the cones is lower than in graphene, thus closer to the ideal linear dispersion. Its structure, formed by a puckered trigonal boron network with hydrogen atoms connected to each boron atom, can be understood as distorted, hydrogenated borophene (Science \textbf{350}, 1513 (2015)). Chemical bonding analysis reveals the boron layer in the network being bound by delocalized four-center two-electron $σ$ bonds. Finally, we suggest high-pressure could be a feasible route to synthesise two-dimensional borane.

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Miguel Martinez-Canales, Timur R. Galeev, Alexander I. Boldyrev, Chris J. Pickard. 2017-11-27. Dirac cones in Two-dimensional Borane. https://doi.org/10.1103/physrevb.96.195442

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