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运用杂化密度泛函方法(DFT)B3LYP,在LANL2DZ赝势基组水平上对Yn(n=2~10)团簇的多种可能初始构型进行了结构优化和频率及光谱分析,根据能量最低原则确认了Yn(n=2~10)团簇没有虚频的基态结构,且计算得到的结构比以往理论计算得到的结构能量更低,Y2振动频率ωe=188.9 cm-1比以往计算值更接近实验值184.4 cm-1,在此基础上研究了团簇的稳定性和极化率,并分析了Yn(n=2~10)团簇的光谱性能。结果表明,Y7为所研究团簇结构转折点,团簇的电子稳定性随着原子数增加而逐渐减弱。振动光谱分析表明,Yn(n=2~10)团簇中具有较高对称性的C2v和Cs点群具有更多的振动模式,而稳定性较强的Y7和Y9在所研究频段内分别有较好的红外和拉曼活性,有明显的共振现象。
Various possible initial configurations of Yn (n = 2 ~ 10) clusters were optimized by hybrid density functional theory (DFT) B3LYP at LANL2DZ pseudopotential grouping level. Based on the energy and spectral analysis, The minimum principle confirms that the Yn (n = 2 ~ 10) clusters have no ground-state structure with an imaginary frequency, and the calculated structure is lower than that calculated by previous theoretical calculations. The Y2 vibrational frequency ωe = 188.9 cm -1 is higher than the previous calculation Closer to the experimental value of 184.4 cm-1. On the basis of this, the stability and polarizability of the clusters were investigated. The spectral properties of Yn (n = 2 ~ 10) clusters were also analyzed. The results show that Y7 is the turning point of the cluster structure studied, and the electronic stability of the cluster decreases with the increase of the number of atoms. Vibrational spectra analysis showed that the C2v and Cs groups with higher symmetry in Yn (n = 2 ~ 10) clusters have more vibrational modes, and the more stable Y7 and Y9 bands have Better infrared and Raman activity, a clear resonance phenomenon.