A DFT based prediction of gold fullerene Au92Si12 with the aid of silicon
A DFT based prediction of gold fullerene Au92Si12 with the aid of silicon
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DOI：
10.1039/c3ra47999d
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发表时间：
2014-01-01
期刊：
影响因子：
3.9
通讯作者：
Dharamvir, Keya
中科院分区：
文献类型：
--
作者：
Gautam, Seema;Goel, Neetu;Dharamvir, Keya
在量子密度泛函理论（DFT）的自旋极化广义梯度近似（GGA）框架下，系统研究了Au_（92）Si_（12）Bucky球的结构演化.从Au-n（n = 1-16）的低能同分异构体开始，我们发现Si作为超价原子，可以以一种以上的价态构型附着在Au团簇上，导致周围Au原子的几种可能的几何排列。一种这样的几何结构具有悬挂在金原子的准平面排列上的Au-Si单元。结果表明，只有当金原子与其它金原子相邻时，才能形成一个五角形的金原子团簇。通过重复这样的准平面团簇，一个稳定的几何形状的金巴基球Au_（92）Si_（12）的结合能每原子（E-b/n）的3.814 eV和HOMO-LUMO间隙（E-g）的0.6 eV已被优化。目前的工作表明，一个令人兴奋的可能性，一个金色的巴基球，具有相同的旋转对称性的C60分子与一个更大的体积。
Structural evolution of the gold Bucky ball Au92Si12 has been studied via a systematic investigation of AunSi clusters within the framework of DFT with spin-polarized generalized gradient approximation (GGA). Beginning with low energy isomers of Au-n (n = 1-16), we find that Si, being hypervalent, can attach onto the Au cluster in more than one valence configuration, leading to several possible geometrical arrangements of surrounding Au atoms. One such geometry has a Au-Si unit dangling over a quasi-planar arrangement of gold atoms. It is observed that a pentagonal unit of gold atoms attached with a Au-Si dangling unit can only exist in the presence of other neighbouring gold atoms to present a quasi-planar cluster. By repeating such quasi-planar clusters, a stable geometry of golden Bucky ball Au92Si12 with a binding energy per atom (E-b/n) of 3.814 eV and a HOMO-LUMO gap (E-g) of 0.6 eV has been optimized. The current work suggests the exciting possibility of a golden Bucky ball that has the same rotational symmetry as the C60 molecule with a much larger volume.