中文摘要：

使用第一性原理方法计算了单原子铜与石墨烯形成的吸附结构的相关性质。首先给出了吸附的几何结构,并讨论了相应的解离势能曲线。同时,也得到了不同吸附位置的结构的热力学稳定性,并估算了不同构型在常温下的热力学几率。此外,根据量子力学理论计算所给出的电子层次上的信息,分析了吸附体的态密度、前线轨道和差分电子密度,进而讨论了铜与石墨烯的轨道相互作用及成键方式。结合能数据表明,铜原子在石墨烯的桥位吸附得到的驻点结构是最稳定的,与中心位吸附结构的热力学几率比为762∶1,说明桥位吸附是占绝对优势的。电子结构分析结果表明,在桥位吸附体系中,材料仍然保持着与基底相似的导电性。此外,在铜/石墨烯桥位吸附体系中,碳的p轨道和铜的d轨道之间的强烈相互作用是铜与石墨烯间成键的根源。

英文摘要：

A theoretical characteristic of a single-atom adsorbed Cu/graphene system was studied by the first-principles method. The geometrical structure of the Cu/graphene system was determined quantum- mechanically and their corresponding dissociation curves were discussed by the potential energy scanning technique. Further, based on the electronic total energy, the thermodynamical stability of this system as well as the thermodynamical distribution was evaluated. According to the computational data, a detailed analysis was performed for the state densities, frontier orbitals, and electronic density differences. By use of the resulting conclusions, the orbital interactions and bonding modes between the Cu atom and gra- phene were discussed in detail. The computed binding energies indicate that the bridge-site adsorption structure has the lowest energy among all optimized stationary points with the ratio of 762：1 for the ther- modynamical branching to center-site structure. This suggests a preponderance of the bridge-site configu- ration. The computed data of electronic structures show that the bridge-site structure keeps the high elec- trical conductivity, similar to graphene. Furthermore, the strong bonding between Cu and graphene de- rives from the strong interaction between the 13 orbitals of carbon and the d orbitals of Cu.