(SiC)_n(n=1～5)团簇的结构与性质的密度泛函理论研究  

Structure and property of (SiC)_n(n=1～5) clusters:a density functional study

作　　者：张梅玲[1,2] 陈玉红[1] 李公平[2] 张材荣[1] 

机构地区：[1]兰州理工大学理学院,兰州730050 [2]兰州大学核科学与技术学院,兰州730000

出　　处：《原子与分子物理学报》2013年第6期917-923,共7页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(10547007);甘肃省科技厅(0910ZTB095)

摘　　要：运用密度泛函理论（DFT）的杂化密度泛函B3LYP方法，在6—31G＊基组水平上对（SIC）n（n=1～5）团簇各种可能的构型进行了几何结构优化，预测了各团簇的最稳定结构．并对最稳定结构的振动特性、成键特性、电荷特性等进行了理论研究．结果表明t（SiC）。团簇形成碳原子骨架，而硅原子生长在碳原子骨架上；在Si和C相互作用形成团簇的过程中，Si原子向C原子有电荷转移，团簇中原子间相互作用呈现共价型；SiC、（SIC）5团簇有相对较高的动力学稳定性；团簇稳定结构的IR最强振动主要是C—Si键的伸缩振动，Raman较强振动均来自C—C键的伸缩振动．Possible geometrical structures and relative stabilities of （（SiC）n（n=1～5） clusters are studied by using the hybrid density functional theory （B3LYP） with 6-31G＊ basis sets. For the most stable iso- mers of （SiC）n（n=1～5） clusters, the electronic structures, vibrational properties, bonds properties and ionization potentials are analyzed. The calculated results show the following tendencies： （SiC）5 clus- ters form the skeleton of carbon atoms, while the growth of silicon atoms on the carbon atom skeleton; the charge transferring occurs between the Si and the C during them forming clusters. The charge trans- fer results in the positive Si atoms and the negative C atoms. The interactions in clusters of atoms are of covalence. The dynamic stabilities of SiC and （SiC）5 clusters are higher than those of other clusters. The strongest IR vibration of theclusters stable structure is the C--Si bond stretching vibration. The strong Raman vibration comes from the C--C bond stretching vibration.

关 键 词：(SiC)n(n=1~5)团簇 密度泛函理论 基态结构 结合能 

分 类 号：O561.1[理学—原子与分子物理]