FeGe_(n)^(0/-)(n=4-16)团簇结构及性质研究

A study on the structure and thermodynamic stability of FeGe_(n)^(0/-)(n=4-16)clusters

使用全局搜索技术结合密度泛函方法TPSSh对FeGe_(n)^(0/-)(n=4-16)团簇的基态结构和性质进行了研究。结果表明阴离子团簇的生长模式为:在n≤8时,为取代结构;当n=9时,团簇形成半笼结构;当n≥10时,为笼型结构。中性团簇的生长模式与阴离子团簇的相同。在确定基态结构的基础上,进一步模拟了阴离子团簇FeGe_(n)^(-)(n=4-16)的光电子能谱(PES),计算了团簇的平均键能(E_(b))、二阶能量差分(Δ^(2)E)、HOMO-LUMO能隙(E_(gap))、自然布局分析(NPA)。结果表明,FeGe_(10)和FeGe_(15)^(-)团簇既具有优良的热力学稳定性又有良好的化学稳定性,可作为新型纳米功能材料最合适的基元。

The ground state structure and properties of FeGe_(n)^(0/-)(n=4-16)clusters were studied by using global search technique combined with density functional theory(TPSSh).The results show that the anion cluster growth mode is:when n≤8,it is a substituent structure;when n=9,the cluster forms a half cage structure;when n≥10,it is a cage structure.The growth mode of neutral clusters is the same as that of anionic clusters.Based on the determination of the ground state structure,the photoelectron spectroscopy(PES)of the anion cluster-FeGe_(n)^(-)(n=4-16)was further simulated,and the average bond energy(E_(b)),the second order energy difference(Δ^(2)E),the HOMO-LUMO energy gap(E_(gap)),and the natural layout analysis(NPA)of the cluster were calculated.The results show that FeGe_(10) and FeGe_(15)^(-)clusters have excellent thermodynamic stability and chemical stability,which can be used as the most appropriate units of new nano functional materials.