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Universal Phase Transitions of AlB2-Type Transition-Metal Diborides.

ABSTRACT: High-pressure phase transitions of AlB2-type transition-metal diborides (TMB2; TM = Zr, Sc, Ti, Nb, and Y) were systematically investigated using first-principles calculations. Upon subjecting to pressure, these TMB2 compounds underwent universal phase transitions from an AlB2-type to a new high-pressure phase tP6 structure. The analysis of the atomistic mechanism suggests that the tP6 phases result from atomic layer folds of the AlB2-type parent phases under pressure. Stability studies indicate that the tP6-structured ZrB2, ScB2, and NbB2 are stable and may be observed under high pressure and the tP6-structured TiB2 phase may be recovered at ambient pressure.

SUBMITTER: Ling F

PROVIDER: S-EPMC7066655 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Universal Phase Transitions of AlB2-Type Transition-Metal Diborides.

Ling Feifei F Luo Kun K Hao Lingjuan L Gao Yufei Y Yuan Zhikang Z Gao Qi Q Zhang Yang Y Zhao Zhisheng Z He Julong J Yu Dongli D

ACS omega 20200228 9

High-pressure phase transitions of AlB2-type transition-metal diborides (TMB2; TM = Zr, Sc, Ti, Nb, and Y) were systematically investigated using first-principles calculations. Upon subjecting to pressure, these TMB2 compounds underwent universal phase transitions from an AlB2-type to a new high-pressure phase tP6 structure. The analysis of the atomistic mechanism suggests that the tP6 phases result from atomic layer folds of the AlB2-type p ...[more]

PMID: 32175508

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