In this paper the elastic and thermodynamic properties of the cubic zinc-blende structure BeS at different pressures and temperatures are investigated by using ab initio plane-wave pseudopotential density functional t...In this paper the elastic and thermodynamic properties of the cubic zinc-blende structure BeS at different pressures and temperatures are investigated by using ab initio plane-wave pseudopotential density functional theory method within the generalized gradient approximation （GGA）. The calculated results are in excellent agreement with the available experimental data and other theoretical results. It is found that the zinc-blende structure BeS should be unstable above 60GPa. The thermodynamic properties of the zinc-blende structure BeS are predicted by using the quasi-harmonic Debye model. The pressure-volume-temperature （P - V - T） relationship, the variations of the thermal expansion coefficient α and the heat capacity Cv with pressure P and temperature T, as well as the Gruneisen parameter-pressure-temperature （γ- P - T） relationship are obtained systematically in the ranges of 0-90GPa and 0-2000K.展开更多
The electronic and optical properties of the cubic zinc-blende （ZB） structured filled tetrahedral semiconductor α-LiZnN under pressure are investigated by using ab initio plane wave pseudopotential density function...The electronic and optical properties of the cubic zinc-blende （ZB） structured filled tetrahedral semiconductor α-LiZnN under pressure are investigated by using ab initio plane wave pseudopotential density functional theory method within the generalized gradient approximation （GGA）.The electronic band structure and the density of state under pressure are systematically described.The basic optical constants,including the reflection and absorption spectra,the energy-loss function,the complex refractive index and the dielectric function,are calculated and analysed at different external pressures.Our results suggested that the ZB α-LiZnN is transparent in the partially ultra-violet to the visible light region,and it seems that the transparency is hardly affected by the pressure.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 10576020)the NSAF (Grant No 10776022)
文摘In this paper the elastic and thermodynamic properties of the cubic zinc-blende structure BeS at different pressures and temperatures are investigated by using ab initio plane-wave pseudopotential density functional theory method within the generalized gradient approximation （GGA）. The calculated results are in excellent agreement with the available experimental data and other theoretical results. It is found that the zinc-blende structure BeS should be unstable above 60GPa. The thermodynamic properties of the zinc-blende structure BeS are predicted by using the quasi-harmonic Debye model. The pressure-volume-temperature （P - V - T） relationship, the variations of the thermal expansion coefficient α and the heat capacity Cv with pressure P and temperature T, as well as the Gruneisen parameter-pressure-temperature （γ- P - T） relationship are obtained systematically in the ranges of 0-90GPa and 0-2000K.
基金Project supported by the National Natural Science Foundation of China (Grant No 10776022)
文摘The electronic and optical properties of the cubic zinc-blende （ZB） structured filled tetrahedral semiconductor α-LiZnN under pressure are investigated by using ab initio plane wave pseudopotential density functional theory method within the generalized gradient approximation （GGA）.The electronic band structure and the density of state under pressure are systematically described.The basic optical constants,including the reflection and absorption spectra,the energy-loss function,the complex refractive index and the dielectric function,are calculated and analysed at different external pressures.Our results suggested that the ZB α-LiZnN is transparent in the partially ultra-violet to the visible light region,and it seems that the transparency is hardly affected by the pressure.
