Sin－1N和Sin－2N2（n=3~9）团簇结构与光振动能谱

用密度泛函理论(Density Functional Theory,DFT)的B3LYP/ 6-311G(d)方法,对Sin－1N和Sin－2N2 (n=3~9)团簇的几何构型、总能量、光振动能谱等性质进行了理论研究.通过对基态结构的几何参量分析发现,对Sin－2N2 (n=3~9)团簇,只有在SiN2和Si2N2结构中N-N成键；n＞4团簇结构,N-N不成键.对团簇能量讨论的结果表明;对于Sin－1N (n=3~9)团簇,总原子数是偶数的团簇比奇数的稳定；对于Sin－2N2(n=3~9)团簇,总原子数是奇数的团簇比偶数的稳定.

Structure and Vibrational Spectroscopy about Sin-1N and Sin-2N2(n=3～9)Clusters

The method of B3LYP/ 6-311G (d) was used to optimize the geometry configuration,total energy and vibrational spectroscopy calculation of Sin－1N and Sin－2N2 (n=3~9) clusters.Analysis of the geometrical parameters of ground state structures show that: in Sin－2N2 (n=3~9) clusters,N－N is exist in SiN2 and Si2N2 cluster,and there is no N-N in Sin－2N2 (n=3~9) clusters when n＞4.From the calculation of chemical thermodynamics,it indicates that the structure with even n is more stable than those with odd n in Sin－1N (n=3~9) clusters;and the structure with odd n is more stable than those with even n in Sin－2N2 (n=3~9) clusters.