title: Phase stability, mechanical properties, hardness, and possible reactive routing of chromium triboride from first-principle investigations.
abstract: The first-principles calculations are employed to provide a fundamental understanding of the structural features and relative stability, mechanical and electronic properties, and possible reactive route for chromium triboride. The predicted new phase of CrB3 belongs to the rhombohedral phase with R-3m symmetry and it transforms into a hexagonal phase with P-6m2 symmetry at 64 GPa. The mechanical and thermodynamic stabilities of CrB3 are verified by the calculated elastic constants and formation enthalpies. Also, the full phonon dispersion calculations confirm the dynamic stability of predicted CrB3. Considering the role of metallic contributions, the calculated hardness values from our semiempirical method for rhombohedral and hexagonal phases are 23.8 GPa and 22.1 GPa, respectively. In addition, the large shear moduli, Young's moduli, low Poisson's ratios, and small B∕G ratios indicate that they are potential hard materials. Relative enthalpy calculations with respect to possible constituents are also investigated to assess the prospects for phase formation and an attempt at high-pressure synthesis is suggested to obtain chromium triboride.
authors.affiliation: Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
authors.forename: Ming-Min
authors.initials: MM
authors.lastname: Zhong
authors.affiliation: Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
authors.forename: Xiao-Yu
authors.initials: XY
authors.lastname: Kuang
authors.affiliation: Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
authors.forename: Zhen-Hua
authors.initials: ZH
authors.lastname: Wang
authors.affiliation: Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Shao
authors.affiliation: Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Ding
authors.affiliation: Physics Department, Sichuan Normal University, Chengdu 610068, China.
authors.forename: Xiao-Fen
authors.initials: XF
authors.lastname: Huang