光学学报, 2014, 34 (3): 0316002, 网络出版: 2014-02-28
Mg2Sin(n=1~9)团簇结构、稳定性与光谱性质的密度泛函理论研究 下载: 760次
Density-Functional Theory Study of the Structural, Stability and Spectrum Properties for Mg2Sin (n=1~9) Clusters
光谱学 Mg2Sin团簇 结构与稳定性 密度泛函理论 spectroscopy Mg2Sin clusters structure and stability density functional theory
摘要
运用密度泛函理论(DFT)中的B3LYP方法,在6-311G (d)基组的水平上对Mg2Sin(n=1~9)团簇的多种可能几何构型进行了结构优化,获得了各个尺寸下团簇的最低能量结构,随后对最低能量构型的稳定性、红外光谱与拉曼光谱性质进行了理论研究。结果发现:当n≥3时,Mg2Sin团簇的基态构型均为立体结构;Mg原子的掺入提高了体系的化学活性;Mg2Si4与Mg2Si6是幻数结构;在相同的观察频段内,Mg2Si4团簇的红外光谱只有一个强振动峰,拉曼光谱强振动峰的个数较多且位于高频段内,其拉曼活性较强,与之相反,Mg2Si6团簇的红外光谱强振动峰个数较多,而拉曼光谱强振动峰则只有一个,表明其红外活性较强。
Abstract
The possible geometrical structures of Mg2Sin(n=1~9) clusters are performed structural optimization by using the density-functional theory (DFT) at the B3LYP/6-311G (d) level. For the lowest energy structures, the stabilities and spectrum properties are investigated. The calculated results indicate that the most stable structures of Mg2Sin clusters favor the three-dimensional structures when n≥3. The impurity magnesium atoms in the Mg2Sin clusters can reduce the chemical stability of silicon cluster with small size. Mg2Si4 and Mg2Si6 are the magic numbers. The number of the infrared vibrational peak for Mg2Si4 cluster is only one, but the Raman vibrational peaks are much more. The Mg2Si4 cluster exhibits strong Raman activity at higher frequency band. On the contrary, Mg2Si6 cluster has more Raman vibrational peaks and one infrared vibrational peak, it exhibits strong infrared activity at the whole frequency band.
张帅, 刘旭焱, 王卓, 李根全, 卢成. Mg2Sin(n=1~9)团簇结构、稳定性与光谱性质的密度泛函理论研究[J]. 光学学报, 2014, 34(3): 0316002. Zhang Shuai, Liu Xuyan, Wang Zhuo, Li Genquan, Lu Cheng. Density-Functional Theory Study of the Structural, Stability and Spectrum Properties for Mg2Sin (n=1~9) Clusters[J]. Acta Optica Sinica, 2014, 34(3): 0316002.