摘要
We put forward a first-principles density-functional theory about the impact of pressure on the structural and elastic properties of bulk CaN2,SrN2 and BaN2.The ground state properties of three alkaline earth diazenides were obtained,and these were in good agreement with previous experimental and theoretical data.By using the quasi-harmonic Debye model,the thermodynamic properties including the debye temperature ΘD,thermal expansion coefficient α,and gruneisen parameter y are successfully obtained in the temperature range from 0 to 100 K and pressure range from 0 to 100 GPa,respectively.The optical properties including dielectric function ε（ω）,absorption coefficient α（ω）,reflectivity coefficient R（ω）,and refractive index n（ω） are also calculated and analyzed.
We put forward a first-principles density-functional theory about the impact of pressure on the structural and elastic properties of bulk CaN2,SrN2 and BaN2.The ground state properties of three alkaline earth diazenides were obtained,and these were in good agreement with previous experimental and theoretical data.By using the quasi-harmonic Debye model,the thermodynamic properties including the debye temperature ΘD,thermal expansion coefficient α,and gruneisen parameter y are successfully obtained in the temperature range from 0 to 100 K and pressure range from 0 to 100 GPa,respectively.The optical properties including dielectric function ε（ω）,absorption coefficient α（ω）,reflectivity coefficient R（ω）,and refractive index n（ω） are also calculated and analyzed.
基金
Funded by the Natural Science Foundation of Education Committee of Anhui Province(No.KJ2016B003)
the National Key Laboratory Fund for Shock Wave and Detonation Physics Research of the China Academy of Engineering Physics(No.9140C671101110C6709)
the Defense Industrial Technology Development Program of China(No.B1520110002)
the National Basic Research Program of China(No.2010CB731600)
