Wang Jinlan, Zhu Liyan, Zhang Xiuyun, Yang Mingli
Department of Physics, Southeast University, Nanjing 211189, China.
J Phys Chem A. 2008 Sep 11;112(36):8226-30. doi: 10.1021/jp803204z. Epub 2008 Aug 14.
The dipole polarizabilities of Co(n)Bz(m), (n, m = 1-4, m = n, n + 1) clusters are studied by means of an all-electron gradient-corrected density functional theory and finite field method. The dipole moments are relatively large for most of the clusters, implying their asymmetric structures. The total polarizability increases rapidly as cluster size, whereas the average polarizability shows "odd-even" oscillation with relatively large values at (n, n + 1). The polarizabilities exhibit clear shape-dependent variation, and the sandwich structures have systematically larger polarizability and anisotropy than the rice-ball isomers. The dipole polarizabilities are further analyzed in terms of the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap, ionization potential, and electron delocalization volume. We conclude that the polarizability variations are determined by the interplay between the geometrical and electronic properties of the clusters.
采用全电子梯度校正密度泛函理论和有限场方法研究了Co(n)Bz(m)（n, m = 1 - 4，m = n, n + 1）团簇的偶极极化率。大多数团簇的偶极矩相对较大，这意味着它们的结构不对称。总极化率随团簇尺寸迅速增加，而平均极化率呈现“奇偶”振荡，在(n, n + 1)时具有相对较大的值。极化率表现出明显的形状依赖性变化，夹心结构的极化率和各向异性比饭团异构体系统地更大。根据最高占据分子轨道 - 最低未占据分子轨道（HOMO - LUMO）能隙、电离势和电子离域体积对偶极极化率进行了进一步分析。我们得出结论，极化率的变化由团簇的几何性质和电子性质之间的相互作用决定。
