氮化硼光频介电常数的计算  

The Computation Study of BN Optical Frequency Coefficient

作　　者：杨保华[1] 李英兰[2] 王红艳[1] 

机构地区：[1]淮北煤炭师范学院物理与电子信息学院,安徽淮北235000 [2]北京理工大学物理系,北京100081

出　　处：《淮北煤炭师范学院学报（自然科学版）》2009年第4期11-15,共5页Journal of Huaibei Coal Industry Teachers College(Natural Science edition)

基　　金：国家自然科学基金项目(50706015);安徽省高校青年教师科研资助项目(2008jql072)

摘　　要：文章采用基于第一原理的赝势平面波的方法获得六方氮化硼层状结构模型和参数;利用介质球模型计算出BN极化率;考虑到离子间距离小于离子本身半径时,就必须对洛仑兹有效电场进行修正,求得洛仑兹有效电场Ee;并结合极化率而求得氮化硼光频介电常数.此计算过程中考虑到电子云的重叠和渗透效应;最后分析不同修正因子λ对结果的影响,将所得计算结果与实际氮化硼光频介电常数进行对比,结果发现,内电场修正因子λ→0时计算结果才与实际情况接近.The structure model and data of the hexagonal lamellar Boron Nitride were studied by using pseudopotential plane - wave method, based on density functional theory. The polarizability of Boron Nitride was computed by the dielectrical ball model; for the BN＇s the low dielectric, the Lorentz effective electric field was modefied by considering the electric cloud overlap and infiltration effect; optical frequency coefficient of the Boron Nitride dielectrical was settled after considering its polarizability and the Lorentz effective electric field. Finally, with different modification factor λ, the result of calculation compares with the practice, it was found that when electric field modification factor λ→0, the computed result was in accordance with the practice.

关 键 词：氮化硼 极化率 电子云重叠效应 洛仑兹有效电场 

分 类 号：TQ343.7[化学工程—化纤工业]