摘要
本文用包含马德隆(Madelung)势的电荷自洽EHT(Extended Huckel Theory)研究对离子晶体(LiF,NaCl和KCl)电子结构的计算。结果表明:6×6×6集团已能较好地模拟真实晶体。由此集团计算所得的禁带和价带宽度与无限晶体的实验结果符合较好。从电子态密度分析可知在禁带中出现了表面态。这些表面态几乎完全来自集团表面碱金属原子的贡献,而且导带底附近的表面态主要来自这些表面原子的s态和部分p态的贡献。
The cluster model calculations of the electronic structure for the ionic crystals (LiF, NaCl and KC1) are carried out by means of the charge self-consistent Extended Huckel Theory (EHT) including the Madelung Potential. The results show that the 6×6×6 cluster can be used to simulate the real crystal. The calculated band gaps and the widths of the valence bands are in good agreement with the experimental data. The total and local density of states display the presence of the sarface states in the band gap. The contribution to the surface states are almost all from the alkali atoms at the surface. The surface states near the bottom of the conduction band are essentially from the s state and a part of p state of the alkali atoms at the surface.
出处
《原子与分子物理学报》
CAS
CSCD
北大核心
1992年第1期2141-2149,共9页
Journal of Atomic and Molecular Physics
