Stability of gold cages (Au16 and Au17) at finite temperature

被引:7
作者
Chandrachud, Prachi [1 ]
Joshi, Kavita [2 ]
Krishnamurty, Sailaja [2 ]
Kanhere, D. G. [1 ,2 ]
机构
[1] Univ Poona, Dept Phys, Pune 411007, Maharashtra, India
[2] Univ Poona, Ctr Modelling & Simulat, Pune 411007, Maharashtra, India
来源
PRAMANA-JOURNAL OF PHYSICS | 2009年 / 72卷 / 05期
关键词
Thermodynamics of clusters; gold clusters; density functional theory; CLUSTERS; PLANAR;
D O I
10.1007/s12043-009-0076-x
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We have employed ab initio molecular dynamics to investigate the stability of the smallest gold cages, namely Au-16 and Au-17, at finite temperatures. First, we obtain the ground state structure along with at least 50 distinct isomers for both the clusters. This is followed by the finite temperature simulations of these clusters. Each cluster is maintained at 12 different temperatures for a time period of at least 150 ps. Thus, the total simulation time is of the order of 2.4 ns for each cluster. We observe that the cages are stable at least up to 850 K. Although both clusters melt around the same temperature, i.e. around 900 K, Au-17 shows a peak in the heat capacity curve in contrast to the broad peak seen for Au-16.
引用
收藏
页码:845 / 855
页数:11
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