MCo_12原子簇的电子结构和磁性性质研究

利用分离变分局域自旋密度泛函方法,对正二十面体MCo12原子簇的电子结构和磁性性质进行了研究,结果表明:原子簇的中心原子与表面原子之间具有键长收缩效应,其相互作用得到了加强;用Ti、V、Cr、Mn、Fe和Ni原子替代中心Co原子后,原子簇的稳定性得到了一定的提高;均呈现出金属特性和一定的磁性,价带宽度随着M原子原子序数的增加而逐渐变宽。该研究将为探索以过渡金属原子簇为基础合成新的特殊功能材料提供重要的理论依据。

Study on the Electronic and Magnetic Properties of MCo_12 Clusters

The stability, electronic and magnetic properties of icosahedral Mco12 clusters are studied by using the discrete variational local-spin-density-function method, Where M=Ti,V,Cr,Mn,Fe,Co and Ni..our calculated results show that all the clusters have bond-length contraction and metallic character , all the clusters are magnetism and the valence-band width(VBW) becomes wider with the increase of atomic number.Some clusters(M=Ti,Mn and Co) have closed electronic shell while the others have open electronic shell and are expected to distort further.the results also indicated that the cluster moment is reduced by the substitution of central Co atom with an M atom and that the average moment per atom of all clusters is larger than that of the bulk Co.Our results compare well with the available experimental results.