Department of Chemistry, College of Sciences, Shiraz University, Shiraz, 71454, Iran.
J Phys Chem A. 2010 Dec 9;114(48):12709-15. doi: 10.1021/jp106772n. Epub 2010 Nov 15.
The static and dynamic polarizabilities for the lowest-energy structures of pure aluminum clusters up to 31 atoms have been investigated systematically within the framework of density functional theory. The size evolution of several electronic properties such as ionization potential, electron affinity, the energy gap between the highest occupied molecular orbital and lowest unoccupied molecular orbital, and chemical hardness have also been discussed for aluminum clusters. Our primary focus in this article, however, has been upon the study of polarizability of aluminum clusters, although we also looked at the role of other electronic properties. From the energetics point of view, the relative stability of aluminum clusters at different sizes is studied in terms of the calculated second-order difference in the total energy of cluster and fragmentation energy, exhibiting that the magic numbers of stabilities are n = 7, 13, and 20. Moreover, the minimum polarizability principle is used to characterize the stability of aluminum clusters. The results show that polarizabilities and electronic properties can reflect obviously the stability of clusters. Electronically, the size dependence of ionization potential and electron affinity of clusters is determined. On the basis of the Wood and Perdew model these quantities converge asymptotically to the value of the bulk aluminum work function.
采用密度泛函理论系统地研究了最低能结构的纯铝团簇（高达 31 个原子）的静态和动态极化率。还讨论了几个电子性质（如电离能、电子亲合能、最高占据分子轨道和最低未占据分子轨道之间的能隙以及化学硬度）的尺寸演化。然而，本文的主要重点是研究铝团簇的极化率，尽管我们也研究了其他电子性质的作用。从能量学的角度来看，根据簇和碎片化能的总能量的二阶差分来研究不同尺寸的铝团簇的相对稳定性，表明稳定性的“魔术数字”为 n = 7、13 和 20。此外，还采用最小极化率原理来表征铝团簇的稳定性。结果表明，极化率和电子性质可以明显反映团簇的稳定性。在电子方面，确定了团簇的电离能和电子亲合能的尺寸依赖性。根据 Wood 和 Perdew 模型，这些量渐近收敛到体铝功函数的值。
