W_6Si_n^(0,±)(n=1,2)团簇结构与电子性质的密度泛函理论研究  

Density functional theory study on the structure and electronic properties of W_6Si_n^(0,±)(n=1,2) clusters

作　　者：张秀荣[1] 刘小芳[2] 康张李[2] 

机构地区：[1]江苏科技大学高等教育研究所,江苏镇江212003 [2]江苏科技大学数理学院,江苏镇江212003

出　　处：《江苏科技大学学报（自然科学版）》2010年第6期619-624,共6页Journal of Jiangsu University of Science and Technology:Natural Science Edition

基　　金：江苏省高校研究生科研创新计划资助项目(CX095_002Z)

摘　　要：利用密度泛函理论中的杂化密度泛函B3LYP,在Lanl2dz基组水平上对W6Sin0,±(n=1,2)团簇的各种可能构型进行了几何结构优化,得出了它们的基态构型,并对基态构型的芳香性、磁性及NBO轨道进行了系统的理论分析.结果表明:所有的W6Sin0,±(n=1,2)团簇的基态及亚稳态结构都为立体几何结构,Si-Si之间不成键;aW6Si20,±团簇具有芳香性,其中aW6Si2团簇的芳香性最强;电荷由Si原子向W原子转移;aW6Si1团簇无磁性,aW6Si1+,aW6Si20,±团簇具有弱的铁磁性,aW6Si1-团簇具有弱的反铁磁性;aW6Si20,±团簇比aW6Si10,±团簇的总磁矩大.The possible equilibrium geometries of WnSi20,±（n=1,2）clusters were optimized by using the density functional theory at the B3LYP/Lanl2dz level.For the ground state structures,the aromaticity,magnetic properties and NBO（natural bonding orbital） were analyzed.The results show that： all the ground state and metastable structures of W6Sin0,±（n=1,2）clusters are three-dimensional without Si-Si bonding in the ground state and metastable structures of W6Si20,±clusters.aW6Si20,±clusters possess aromaticity with aW6Si2 cluster being the most aromatic.The charge transfers from Si atom to W atom.aW6Si1 cluster is non-magnetic.aW6Si1＋cluster and aW6Si20,±clusters are weakly ferromagnetic,whereas aW6Si1-cluster is weakly anti-ferromagnetic.aW6Si20,±clusters enhance magnetic moments as compared to aW6Si10,±clusters.

关 键 词：W6Sin0 ±(n=1 2)团簇 结构与电子性质 密度泛函理论 

分 类 号：O641[理学—物理化学]