title: First-principles investigation on elastic and thermodynamic properties ofPnnm-CN under high pressure.
abstract: The elastic anisotropy and thermodynamic properties of the recently synthesizedPnnm-CN have been investigated using first-principles calculations under high temperature and high pressure. The calculated equilibrium crystal parameters and normalized volume dependence of the resulting pressure agree with available experimental and theoretical results. Within the considered pressure range of 0-90 GPa, the dependences of the bulk modulus, Young's modulus, and shear modulus on the crystal orientation forPnnm-CN have been systematically studied. The results show that thePnnm-CN exhibits a well-pronounced elastic anisotropy. The incompressibility is largest along thec-axis. For tension or compression loading, thePnnm-CN is stiffest along [001] and the most obedient along [100] direction. On the basis of the quasi-harmonic Debye model, we have explored the Debye temperature, heat capacity, thermal expansion coefficient, and Grüneisen parameters within the pressure range of 0-90 GPa and temperature range of 0-1600K.
authors.affiliation: College of Physics & Optoelectronics Technology, Baoji University of Arts and Sciences , Baoji 721016, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Ya-Ru
authors.affiliation: School of Electrical and Electronic Engineering, Baoji University of Arts and Sciences , Baoji 721016, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Hai-Rong
authors.affiliation: College of Physics & Optoelectronics Technology, Baoji University of Arts and Sciences , Baoji 721016, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Gang-Tai
authors.affiliation: School of Sciences, Xidian University , Xi'an 710071, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Qun
authors.affiliation: School of Physics and Electronic Engineering, Sichuan University of Science & Engineering , Zigong 643000, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yu-Quan