团簇Fe3Cr3的磁学性质

Magnetic properties of cluster Fe3Cr3

以团簇Fe3Cr3为模型,采用密度泛函理论中的B3LYP/Lan12dz方法对设计出的初始构型进行优化计算得到14种优化构型,从电子自旋态密度图和磁矩等角度对具有磁性的8种三重态构型展开研究,发现团簇Fe3Cr3三重态优化构型的磁性主要由d轨道上的成单α电子贡献,p轨道为次要贡献者,能量较低的s轨道则不易存在成单电子,但也有极少贡献;对各原子的磁矩进行分析发现,Fe原子和Cr原子在团簇Fe3Cr3不同能量范围内的三重态优化构型中对磁性的作用效果和作用强度都不同;在原子磁矩正负分布情况相同的构型中,能量较低者其磁矩分布范围普遍大于能量较高者,且原子磁矩的分布范围在构型5(3)最大,构型4(3)次之。

Taking cluster Fe3Cr3 as a model,14 optimized configurations were obtained from the designed initial configurations by using B3LYP/Lan12dz method in density functional theory.The magnetic properties of eight configurations in triplet state were studied from the aspect of density of states of electrons spinning and magnetic moment.It is found that the magnetism of the optimized triplet configurations of cluster Fe3Cr3 is mainly contributed by unpaired alpha electrons in d orbital,and the p orbital is a secondary contributor.Unpaired electrons are uneasy to exist in s orbital which has lower energy but still make a little contribution to the magnetism.From the analysis of the magnetic moments of each atom it was found that the effect and intensity of Fe atom and Cr atom on magnetism of configurations in triplet state with different energy of cluster Fe3Cr3 are different.In the configurations with the same positive and negative distributions of atomic magnetic moment,the distribution range of magnetic moment in the lower energy group is generally larger than that in the higher energy group,and in the configuration 5(3),the distribution range of atomic magnetic moment is the largest,followed by that in the configuration 4(3).