W_mB_n(m+n≤7)团簇电子结构与光谱性质的计算研究

Calculation study on the electronic structure and spectroscopic properties of W_mB_n (m+n≤7) clusters

采用密度泛函理论中的B3LYP方法,在LANL2DZ基组水平上优化了WmBn(m+n≤7)团簇的几何结构,得到了它们的基态构型,并对其自然键轨道(natural bond orbital,NBO)以及振动光谱进行了计算研究.结果表明:团簇中NBO电荷分布状况与团簇的对称性相关;W原子比B原子电荷调节能力强,易与其他原子形成化学键;最大频率以及最强峰值对应的振动模式大部分是B原子或W原子的伸缩振动以及摇摆振动.

Geometric structures of WmBn （m＋n≤7） clusters are optimized by using the density functional theory at the B3LYP/LANL2DZ level.For the ground state configurations , the polarizability, magnetism,NBO（natural bond orbital ） and vibrational spectrum are analyzed .The calculated results show that the charge distribution of NBO is related to the symmetry of cluster;W charge regulation capability is better than B , which is easy to form chemical bonds;the strongest peak vibration mode corresponds to stretching or wagging vibration of atom B or W .