A_nC_2(A=Fe,Co,Ni,Cu)团簇的密度泛函研究(英文)

A Density Functional Study of A_nC_2(A=Fe,Co,Ni,Cu) Clusters

采用平面波基矢及超软赝势使用密度泛函理论方法详细地研究了AnC2(A=Fe,Co,Ni,Cu,n=1-3)团簇的几何结构,结合能和磁性.对双原子分子团簇(A2及AC)所得结果与以往的实验和计算结果基本一致.除了Fe3C2和Co3C2的基态几何结构是三角双锥之外,其他混合团簇的基态几何结构都是平面构型.计算结果表明,加入碳原子会增加An团簇的稳定性,在AnC2团簇中,An(A=Fe,Co,Ni)与C2的相互作用相比Cun和C2的相互作用要强.

Geometrical structures, binding energies and magnetic moments of AnC2（A=Fe, Co, Ni, Cu, n = 1 --3） clusters were studied by using the density functional theory with the plane wave basis sets and ultrasoft pseudopotentials. Our results for the dimers （A2 and AC） are generally in good agreement with available experiment data and previous theoretical data. All the ground state geometrical structures of these metal-carbon clusters are found to be planar except Fe3C2 and Co3C2 which show trigonal bipyramid structures. Our results show that the doping of carbon atoms improves the stability of An clusters, and the interaction strength between C2 and An（A=Fe, Co, Ni） in A.C2 clusters are much stronger than the interaction strength between C2and Cun in CunC2 clusters.