摘要
本文应用PS-HONDO方法研究了MoO_3在SiO_2及γ-Al_2O_3表面分散特征的差别,从其原子簇模型的势能曲线、成键键能、电荷分布、键级和轨道组成等方面进行了分析。结果表明:对于表面四面体配位的钼模型而言,MoO_3可在γ-Al_2O_3表面呈单分子层分散,与γ-Al_2O_3表面有较强的成键作用;而在SiO_2表面则不能分散,几乎不与SiO_2表面成键。从而较好地从理论上解释了部分实验现象,为应用量子化学方法研究一种氧化物在另一种氧化物上的分散行为的微观机制提供了一个良好的开端和有益的启示.
The characteristic difference of MoO_3 dispersing on SiO_2 and γ-A1_2O_3 surfaces was studied with PS-HONDO method. From the potential energy curves, atomic charge distributions, bond orders and orbital components of the cluster models, we obtained the following conclusions: MoO_3 could disperse on γ-A1_2O_3 surface as a monolayer form, there is a strong interaction between MoO_3 and γ-Al_2O_3; on SiO_2 surface, however, MoO_3 could not disperse as a monolayer form, it exists on the surface only in bulk phase. This calculated results could explain some experimental phenomena observed by many researchers.
基金
国家自然科学基金
