Ting Elvis C M, Popa Tatiana, Paci Irina
Department of Chemistry, University of Victoria, Victoria, BC, V8W 3V6, Canada.
Beilstein J Nanotechnol. 2016 Jan 18;7:53-61. doi: 10.3762/bjnano.7.6. eCollection 2016.
The adsorption of organic molecules on metal surfaces has a broad array of applications, from device engineering to medical diagnosis. The most extensively investigated class of metal-molecule complexes is the adsorption of thiols on gold.
In the present manuscript, we investigate the dependence of methylthiol adsorption structures and energies on the degree of unsaturation at the metal binding site. We designed an Au20 cluster with a broad range of metal site coordination numbers, from 3 to 9, and examined the binding conditions of methylthiol at the various sites.
We found that despite the small molecular size, the dispersive interactions of the backbone are a determining factor in the molecular affinity for various sites. Kink sites were preferred binding locations due to the availability of multiple surface atoms for dispersive interactions with the methyl groups, whereas tip sites experienced low affinity, despite having low coordination numbers.
有机分子在金属表面的吸附有着广泛的应用，从器件工程到医学诊断。研究最为广泛的一类金属 - 分子络合物是硫醇在金上的吸附。
在本论文中，我们研究了甲硫醇吸附结构和能量对金属结合位点不饱和度的依赖性。我们设计了一种金20团簇，其金属位点配位数范围从3到9，并研究了甲硫醇在不同位点的结合条件。
我们发现，尽管分子尺寸小，但主链的色散相互作用是分子对不同位点亲和力的决定性因素。扭结位点是优先的结合位置，因为有多个表面原子可用于与甲基进行色散相互作用，而尖端位点尽管配位数低，但亲和力也低。
