MCo12原子簇的電子結(jié)構(gòu)和磁性性質(zhì)研究

利用分離變分局域自旋密度泛函方法，對(duì)正二十面體MCo12原子簇的電子結(jié)構(gòu)和磁性性質(zhì)進(jìn)行了研究，結(jié)果表明：原子簇的中心原子與表面原子之間具有鍵長收縮效應(yīng)，其相互作用得到了加強(qiáng)；用Ti、V、Cr、Mn、Fe和Ni原子替代中心Co原子后，原子簇的穩(wěn)定性得到了一定的提高；均呈現(xiàn)出金屬特性和一定的磁性，價(jià)帶寬度隨著M原子原子序數(shù)的增加而逐漸變寬。該研究將為探索以過渡金屬原子簇為基礎(chǔ)合成新的特殊功能材料提供重要的理論依據(jù)。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.