非晶态合金Co_3B_2稳定结构、组成和电子性质

利用密度泛函理论(DFT)方法,在B3LYP/Lan12dz水平下,对设计出的十几种可能存在的构型分别在二、四重态下进行了全参数优化计算和频率验证,最终获得了6种稳定构型,其中二重态2种,四重态4种。对这些稳定构型的能量、组成和电子性质进行分析,结果表明:团簇Co_3B_2能够稳定存在的几何构型有平面形、三角双锥、单"帽"三角锥和变形四方锥;其中具有单"帽"三角锥结构的构型1~(2)最为稳定;团簇构型随能量的逐渐升高,所占比例逐渐下降,其中构型1~(2)所占比例最大,为27.11%;Co和B原子的电子得失与团簇Co_3B_2构型和重态密切相关;Co原子的3d,4s轨道对原子间成键有较大贡献。

Study on stable structure,composition and electron property of amorphous alloy Co3B2

With density functional theory at B3LYP/Lan12dz level,more than ten different configurations of clusters Co3B2,which are likely to exist,are optimized and analyzed in duplicate and quadruple states respec-tively,and six stable configurations are obtained. The energies,compositions,electron properties and catalyt-ic properties in duplicate and quadruple states are analyzed and discussed in detail. The results showed that:the cluster Co3B2 existed stably in configuration of flat pentagon,triangle dipyramid,triangle pyramid with hat and tetragonal pyramid .The most stable configuration was 1(2) of triangle pyramid with hat and it took the largest percentage in the different configurations. With the increase of the energy of each configuration,its per-centage gradually decreased. Whether gain or lose of the Co atoms and B atoms,electrons are decided by the configuration and multiplicity of clusters Co3B2. In clusters Co3B2,the 3d and 4s orbital of Co atoms had great contribution to bonding between atoms.