团簇CoMg2B2的结构稳定性、成键及电子性质研究

Structural stability,bonding and electronic properties of cluster CoMg2B2

在B3LYP/Lan12dz水平下分别以二、四重态对团簇CoMg2B2存在的所有构型进行全参数优化.排除虚频和相同构型后,得出7种优化构型.其中,二重态构型4种,四重态构型3种.对团簇CoMg2B2分析后得到以下结论:构型1(2)和1(4)分别是二重态和四重态下最稳定结构;Mg-B键和Co-B键有较强的成键作用;不管是二重态构型还是四重态构型,Co-B键和B-B键的键级都有一定的拮抗作用;所有构型的电子都是由Mg原子流向Co原子和B原子;优化构型中电子流动性大小的排序为:4^(2)>3^(4)>2^(4)>3^(2)>1^(4)>1^(2)>2^(2).

At the level of B3LYP/Lan12dz,all the configurations of the cluster CoMg2B2 were optimized by two or four states,respectively.By excluding imaginary frequency and the same configuration,seven optimal configurations were obtained.Among them,there are 4 duplex configurations and 3 quadruple configurations.The following conclusions are drawn:Configuration 1(2)and 1(4)are the most stable structures in the duplex and quadruplet states,respectively;Mg-B bond and Co-B bond have strong bonding effect;whether duplex or quadruplet configuration,the bond levels of Co-B bond and B-B bond have certain antagonism.The order of electronic fluidity in the optimized configuration is 4^(2)>3^(4)>2^(4)>3^(2)>1^(4)>1^(2)>2^(2).