Ga_2As_n离子团簇结构及其光电子能谱研究  

Structure and Photoelectron Energy Spectrum of Ga_2As_n Ion Clusters

作　　者：马德明[1] 施卫[1] 李恩玲[1] 侯利平[1] 戴元滨[1] 

机构地区：[1]西安理工大学理学院,陕西西安710048

出　　处：《光学学报》2009年第4期1032-1037,共6页Acta Optica Sinica

基　　金：国家973计划(2007CB310406);国家自然科学基金(50837005;10876026;10876025);西安理工大学创新基金(108-210705)资助

摘　　要：利用密度泛函理论中B3LYP方法,在6—311G(d)基组上对Ga_2 As_n(n=1—5)阴阳离子团簇的几何结构和光电子能谱进行了系统研究。结果得到了各团簇的最稳定结构,在Ga_2As_n(n=1—5)阴阳离子团簇中,稳定性随着总原子数的增大而呈奇偶变化规律,对于Ga_2As_n^-团簇,总原子数为奇数的团簇比原子数为偶数的团簇稳定;对于Ga_2As_n^+团簇,总原子数为偶数的团簇比原子数为奇数的团簇稳定。团簇的最高占据轨道(HOMO)和最低空轨道(LUMO)能级之间的能隙差随As原子数的增大而呈现奇偶交替变化规律,当As原子数为偶数时,中性团簇及其阴阳离子团簇的基本相同,当As原子数为奇数时,它们差异较大。The method of B3LYP/6 - 311G （d） in density functional theory （DET） was used to optimize the geometric configuration and study the photoelectron energy spectrum of Ga2 As,, （n=1- 5） ion clusters. The ground-state structure of the clusters has been obtained, the stability of which shows a certain degree of even/odd alternation with the increase of the total atoms number. The structure with odd number of total atoms is more stable than those with even number of total atoms in Ga2Asn^- clusters, while it is quite the contrary in Ga2Asn^＋ clusters. The energy gap between the highest-occupied molecular orbital （HOMO） and the lowest-unoccupied molecular orbital （LUMO） displays a certain degree of even/odd alternation, with the increase of the arsenic atoms number. The energy gap values with even number of arsenic atoms are b;sically the same, hut they are rather different with odd number of arsenic atoms.

关 键 词：离子团簇 密度泛函理论 结构与稳定性 光电子能谱 

分 类 号：O561[理学—原子与分子物理]