Adatom mediated adsorption of N-heterocyclic carbenes on Cu(111) and Au(111)
Adatom mediated adsorption of N-heterocyclic carbenes on Cu(111) and Au(111)
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DOI：
10.1002/jcc.26801
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发表时间：
2021-12-30
影响因子：
3
通讯作者：
Aldahhak, Hazem
中科院分区：
文献类型：
--
作者：
Jain, Mitisha;Gerstmann, Uwe;Aldahhak, Hazem
用密度泛函理论研究了N-杂环卡宾在Cu（111）和Au（111）表面的吸附.的分子侧基的作用，以及在确定的吸附几何形状的表面形态进行了详细探讨。如对于具有相对小的侧基的NHC在实验中观察到的，平坦的NHC由吸附原子处的吸附产生，并且产生所谓的球形机器人构型，其比在平坦表面上的吸附更稳定，并且为形成双（NHC）二聚体提供有效的前体。在Au（111）上，所得的（NHC）（2）Au络合物是纯物理吸附的，因此是移动的。相比之下，在更具反应性的Cu（111）上，（NHC）（2）Cu二聚体中的中心Cu原子仍然共价键合到表面，导致迁移率，其必须被热活化。
The adsorption of N-heterocyclic carbenes (NHCs) on Cu(111) and Au(111) surfaces is studied with density-functional theory. The role of the molecular side groups as well as the surface morphology in determining the adsorption geometry are explored in detail. Flat-laying NHCs, as observed experimentally for NHC with relatively small side groups, result from the adsorption at adatoms and give rise to the so-called ballbot configurations, which are more stable than adsorption on flat surfaces and provide an efficient precursor for the formation of bis(NHC) dimers. On Au(111), the resulting (NHC)(2)Au complexes are purely physisorbed and thus mobile. On the more reactive Cu(111), in contrast, the central Cu atom in the (NHC)(2)Cu dimer is still covalently bound to the surface, resulting in a mobility, which has to be thermally activated.