(TiZr)_n(n=1～7)团簇的几何构型与性质的密度泛函研究  

DFT study on the structures and properties of(TiZr)_n(n=1～7) clusters

作　　者：王青[1] 李强[1] 戴剑锋[1] 郭永庆[1] 

机构地区：[1]兰州理工大学理学院,兰州730050

出　　处：《原子与分子物理学报》2012年第3期437-444,共8页Journal of Atomic and Molecular Physics

基　　金：国家自然基金项目(50873047);甘肃省教育厅基金项目(0903-12)

摘　　要：采用密度泛函DFT中的B3LYP方法,选择LANL2DZ基组,对(TiZr)_n(n=1～7)团簇的各种可能构型进行了优化,得到了各团簇的最稳定结构,并对最稳定结构的几何结构、IR光谱、成键特性和稳定性等进行了理论分析.结果表明:(TiZr)_n(n=2～7)团簇易形成笼状结构,Ti原子易于得到电子,而Zr原子易于失去电子;体系随着原子数的增多,自由度增加,IR光谱表现出宽带谱特征;定域化轨道标识函数图揭示了(TiZr)_n(n=1～7)基态团簇原子间多为金属键作用,在特定结构下有共价键成分出现;随着原子数增加,(TiZr)_n(n=1～7)团簇带隙减小,金属性增强;(TiZr)_1和(TiZr)_3团簇具有相对较高的动力学稳定性.Possible geometrical structures and relative stabilities of （TiZr）n（n= 1-7） clusters are studied by using the B3LYP method of density functional theory with LANL2DZ basis sets. For the most stable isomers of （TiZr）n（n=l-7） clusters, the electronic structure, infrared spectrum, bonds properties, and relative stabilities are analyzed. The results reveal that the Ti and Zr atoms bonded each other to form a cage structure of the most stable isomers for （TiZr）n（n=2-7） clusters. The population analysis suggests the Ti atoms get easily the electrons and Zr atoms have a tendency to lose the electrons. Infra- red spectrum of the system exhibits broadband because of the increasing number of atoms and freedom of motion. Localized orbital locator analysis reveals that chemical bond mainly is metallic bonds between the atoms in most models, but covalent bonds in a few cases. With increasing in the number of atoms, （TiZr） n（n= 1-7） clusters decrease sharply band gap, metallic-like features are shown. The dynamic stability of （TiZr）l and （ TiZr）a clusters is higher than that of other clusters.

关 键 词：(TiZr)n 团簇 密度泛函理论 结构与性质 

分 类 号：O482[理学—固体物理]