VB2n-(n=8~12)团簇几何结构、电子及热力学特性的理论研究

基于卡里普索结构预测程序和密度泛函理论的第一性原理计算，搜索确定了VB_2n^-（n=8~12）团簇的基态和亚稳态结构。结果发现，V原子的掺杂完全改变了原硼团簇的结构并提高了原体系的稳定性。掺杂体系基态结构分别呈现高对称性的鼓状（VB₁₆^-：C_2v）、管状（VB₁₈^-：C_2v和VB₂₀^-：C_s）及笼状（VB₂₂^-：C₂和VB₂₄^-：D_3h）结构。基于基态结构，研究了体系的电荷转移和极化率，拟合出了光电子能谱、红外和拉曼谱图，分析了流变键和芳香特性。最后，研究了体系的热力学特性，讨论了温度对热力学参数的影响。

Theoretical Study on Geometric Structures, Electronic, and Thermodynamics Properties of VB2n- (n=8-12) Clusters

The geometric structures, electronic, and thermodynamic properties of vanadium doped boron clusters, VB_2n^- (n=8-12), were investigated systemically by using CALYPSO searching method and density functional theory. It is found that vanadium atom doping significantly modifies the structures of the boron clusters and strong the chemical activity of systems. A drum-shaped structure is the global minimum for VB₁₆^- cluster with C_2v point symmetry. Tubular-shaped VB₁₈^- and VB₂₀^- with C_2v and C_s symmetry exhibit a metal-centred tubular with a B₂ unit over the B₁₆ and B ₁₈ drum, respectively. For VB₂₂^- and VB₂₄^- clusters, vanadium atom tends to encapsulate into boron cages. Based on the lowest energy structures, the charge transfer and polarizability were explored, the photoelectron spectra, infrared spectra, and Raman spectra were simulated, the fluxional bonds and aromatic properties were analyzed. At last, the thermodynamic properties were investigated, the thermodynamics parameters were discussed for the lowest energy structures of VB_2n^- (n=8-12) clusters.