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Phase transition and electronic properties of Co-As binary compounds at high pressure.

ABSTRACT: New stable stoichiometries in the Co-As system are investigated up to 100 GPa by the CALYPSO structure prediction method. In particular, we found three novel stable compounds of Co₂As-Pnma, CoAs₂-Pnnm, and CoAs₃-C2/m at high pressure. According to the theoretical electronic band structures, the structures of Co₂As-Pnma, CoAs₂-Pnnm, and CoAs₃-C2/m have metallic characters, and a pressure-induced electronic topological transition was found in CoAs₃-C2/m, which is not shown in other stoichiometries of the Co-As system. The calculated results of the electron localization function show that there are polar covalent bond interactions between Co atoms and As atoms in CoAs₂-Pnnm and CoAs₃-C2/m. The present results can be helpful for understanding diverse structures and properties of Co-As binary compounds under high pressure.

SUBMITTER: Zhang A

PROVIDER: S-EPMC9210071 | biostudies-literature |

REPOSITORIES: biostudies-literature

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