Structures and thermodynamic properties of ZnSe

Through adopting first-principles plane-wave ultrasoft pseudopotential method of density functional theory,the structures and thermodynamic properties of ZnSe were studied.The calculated lattice parameters,bulk modulus and the first order pressure derivative of bulk modulus are agree with the experimental data and other calculated results.By using the quasi-harmonic Debye model,Debye temperature and heat capacity under different temperatures and pressures were successfully obtained.It is appeared that when the applied pressure is increasing,the Debye temperature increases,while the heat capacity shows an opposite trend.The relative lattice parameters and relative volume,the bulk modulus,thermal expansion versus temperature and pressure were also investigated.