C@M_(12)(M=Fe,Co,Ni)团簇稳定性与能量特征的密度泛函理论研究(英文)

Stabilities and Energetic Properties of C@M_(12) (M=Fe,Co,Ni) Clusters:a Density-functional Study

在密度泛函理论框架下采用广义梯度近似和赝势平面波方法,研究了掺碳团簇C@M_(12)(M=Fe,Co,Ni)的能量特性.所得结果表明:用碳原子替换一个金属原子将提高团簇的稳定性.碳原子在表面的结构比其在中心的结构更稳定,这与块体或大尺寸团簇情况相反.通过分析不同碳掺杂结构的能量分布,发现碳原子在这些过渡金属团簇中的熔解率大小的序列与其在块体中相同.

The energetic properties of carbon doped C@M12 （M：Fe, Co, Ni） clusters are investigated using the density-functional theory calculations within the generalized gradient approximation and pseu- dopotential plane wave approach. It is found that substituting a metal atom by carbon enhances the stability of the metal cluster. Clusters with a central carbon atom are all energetically unfavorable as comparing the structures with a surface carbon atom, which is in controversy to the case in solid or very larger clusters where carbon atoms can dissolve. From analyzing the energy distribution of different carbon-doped struc- tures, it seems that same order of carbon solubilities holds in these transition metal clusters as well as in their solids.