原子簇Co2MnB2的稳定结构及成键性质

利用密度泛函理论方法,在B3LYP/Lan12dz水平下,以三角双锥型、四方锥型和平面五边形对原子簇Co2MnB2进行构造,对所构造出的十余种可能构型分别在二、四重态下进行全参数优化计算和频率验证,最后二重态获得四种稳定构型,四重态只有一种稳定构型.对这些稳定构型的几何结构、能量和成键性质进行分析.结果表明：原子簇Co2MnB2的稳定构型均为立体构型.其中,以Mn和双B原子为构型三角平面、双Co原子占据两锥位置的三角双锥构型1（2）最为稳定.金属-类金属键是构型稳定性的主要贡献者.构型随着B-B键长的减小、键级的增大,其稳定性越好;类金属B原子对各构型的稳定性有着极大的辅助调节作用.

Stable configurations and bonding properties of cluster Co2MnB2

More than ten different configurations of cluster Co2MnB2 with doublet and quadruplet multiple states are calculated under the B3LYP/Lanl2dz level by using the Density Functional Theory （DFT） method. After the frequencies of each configuration are verificated, four stable configurations with doublet multiple states and only one stable configuration with quadruplet multiple states are obtained. The geometric struc- tures, energy and bonding properties of these stable configurations are also analyzed respectively. The results of the analysis show that all of the stable configurations of cluster Co2MnB2 are spatial structures. The configu- ration 1 ~2） which is a triangle dipyramid with the same nuclear atoms Co on the dipyramid is the most stable structure of the cluster Co2MnB2. The bond Co-B and Mn-B play an important role on the stability of all config- urations. With the decrease of the B-B bond length and the increase of its bond order, the stability of the con- figurations is better. The metalloid atom B has a regulation effect on the stability of all configurations.