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Pressure-induced metallization in solid boron

Jijun Zhao·Jian Ping Lu
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Abstract

Different phases of solid boron under high pressure are studied by first principles calculations. The $α$-B$_{12}$ structure is found to be stable up to 270 GPa. Its semiconductor band gap (1.72 eV) decreases continuously to zero around 160 GPa, where the material transforms to a weak metal. The metallicity, as measured by the density of states at the Fermi level, enhances as the pressure is further increased. The pressure-induced metallization can be attributed to the enhanced boron-boron interactions that cause bands overlap. These results are consist with the recently observed metallization and the associated superconductivity of bulk boron under high pressure (M.I.Eremets et al, Science{\bf 293}, 272(2001)).

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Jijun Zhao, Jian Ping Lu. 2001-09-28. Pressure-induced metallization in solid boron. https://doi.org/10.1103/physrevb.66.092101

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