闪锌矿型ZnS的电子结构与热力学性质的研究

Study of the electronic structure and thermodynamic properties of zinc blender ZnS

利用第一性原理超软赝势平面波的方法,对闪锌矿ZnS晶体结构进行了几何优化,得到晶格参数为0.5413nm;在优化结构的基础上计算了电子结构,证明闪锌矿ZnS为直接带隙半导体,带隙为2.213eV;零温零压下的弹性常数为C11=98.04GPa、C12=55.34GPa、C44=48.49GPa及弹性模量B0=69.57GPa;根据德拜模型近似,由弹性常量计算了德拜温度为358.5K,并进一步得到摩尔定容热容随温度的变化关系,在高温下,热容接近杜隆—珀蒂极限.

Through first-principles plane-wave ultrsoft pseudopotential method of density functional theory, this paper studies electronic structure, elastic constants and thermodynamic properties of Zinc Blender ZnS. The results of calculation are obtained： lattice parameter is 0. 5413nm; energy gap is 2. 213eV; elastic constant is C11=98. 04Gpa, C12= 55.34Gpa, C44=48. 49GPa, bulk modulus（B） is 69.57GPa; the Debye temperature is 358.5K at the OK and P=0GPa; the heat capacity at different temperature, we find the heat capacity is close to the Dulong-Peti limit at high temperature.