MoSi₂价电子结构分析及结合能计算

来源期刊：中国有色金属学报2007年第2期

论文作者：彭可 易茂中 陶辉锦 冉丽萍

文章页码：216 - 216

关键词：二硅化钼；价电子；结合能；脆性；

Key words：molybdenum disilicide; valence electron; cohesive energy; brittleness

摘    要：根据固体与分子经验电子理论，通过键距差(BLD)方法，计算了金属间化合物MoSi₂的价电子结构和理论结合能。结果表明，MoSi₂理论结合能为1 677.1 kJ/mol，与实验值吻合。由于Si原子偏移，沿〈001〉方向分布的Si—Si原子键共价电子数最多，n_D=0.402 04。MoSi₂晶体中含有较高密度的晶格电子，使MoSi₂具有良好的导电性。MoSi₂晶体中键络分布不均匀性是导致晶体脆性的主要原因。

Abstract: According to the empirical electron theory of solid and molecule, the valence electron structure and theoretical cohesive energy of MoSi₂ were calculated by the BLD method. The results show that the theoretical cohesive energy of MoSi₂ is 1 677.1 kJ/mol, which agrees well with the experimental data. Because of a shift in Si positions, the valence electrons between Si—Si atoms along <001> direction are the most (n_D = 0.402 04). There are lattice electrons with higher densities in MoSi₂, which accounts for the good conductivity of MoSi₂. Also, it is speculated that the brittleness of MoSi₂ can be explained primarily by a heterogeneity of bond distribution.

基金信息：国家自然科学基金资助项目
教育部博士点基金资助项目