First-principles study of elastic and electronic properties of layered ternary nitride SrZrN₂ under pressure

ABSTRACT

The structural, elastic, and electronic properties of SrZrN₂ under pressure up to 100 GPa have been carried out with first-principles calculations based on density functional theory. The calculated lattice parameters at 0 GPa and 0 K by using the GGA-PW91-ultrasoft method are in good agreement with the available experimental data and other previous theoretical calculations. The pressure dependence of the elastic constants and the elastic-dependent properties of SrZrN₂, such as bulk modulus B, shear modulus G, Young's modulus E, Debye temperature Θ, shear and longitudinal wave velocity V_S and V_L, are also successfully obtained. It is found that all elastic constants increase monotonically with pressure. When the pressure increases up to 140 GPa, the obtained elastic constants do not satisfy the mechanical stability criteria and a phase transition might has occurred. Moreover, the anisotropy of the directional-dependent Young's modulus and the linear compressibility under different pressures are analysed for the first time. Finally, the pressure dependence of the total and partial densities of states and the bonding property of SrZrN₂ are also investigated.

KEYWORDS:

• SrZrN₂
• density functional theory
• elastic properties
• electronic structure

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors would like to thank the support by the National Natural Science Foundation of China [grant numbers 11805151, 11405127, and 11747110], the Doctoral Scientific Research Foundation of Xi'an University of Science and Technology [grant number 6310118029], the Scientific Fostering Foundation of Xi'an University of Science and Technology [grant number 201709], and the Science and Technology Tackling Project of the Education Department of Henan Province [grant number 172102210072].