The Study On The Structure And Property Of Tb Doped Silicon Clusters

As a semiconductor material, silicon has played a very important role in modern microelectronics industries, therefore silicon clusters have been extensively studied in both experimental and theoretical aspects. After a metal atom doped in silicon clusters, silicon clusters have better features, and become a new functional materials primitives. In Inner Mongolia, the soil resource is rich in rare earth elements. In this work, a silicon cluster doped with a rare earth metal terbium is acted as the research object. Not only the special nature of silicon clusters doped with metal atoms such as catalytic, biological activity, and electromagnetic properties can be explained, but also the surface reconstruction of silicon clusters caused by doping with metal atom and diffusion effect prototypes of metal atom can be provided by studying the geometric and electronic structures and other thermodynamic properties.The B3LYP method combined with frozing outer layer28electron effective core potential basis set (GENECP basis set) was exployed in this work. The geometries and properties of TbSin (n=1-10) were studied systematically. Their ground state structures were predicted, and their spin multiplicities, resonant frequencies, adiabatic electron affinities, dissociation energies were calculated.In B3LYP/GENECP level, the optimizedground state of neutral TbSin(n=1-10) are C∞v(8∑), C2v(6B1), C2v(8A1), C2v(8B2), Cs(6A’), C2v(6A1), C1(8A), C2v(6A2), Cs(8A"), Cs(8A’), and those of the anions are C∞v(5∏),C2v(5B2),Cs(7A’),C1(7A),Cs(7A"),C2v(7A1),Cs(5A’), C2v(7A2),Cs(7A"), CS(7A"). The generation pattern of the ground state structure was analyzed and the searching method for the ground state structure was explored. In this work, the adiabatic electron affinities for TbSin(n=1-10) were calculated. The values have been predicted to be0.96eV(TbSi),0.44eV(TbSi2),1.34eV(TbSi3),1.21eV(TbSi4),1.62eV(TbSi5),1.50eV(TbSi6),2.07eV(TbSi7),1.68eV(TbSi8),2.08eV(TbSi9),1.87eV(TbSi10) respectively. It is found that when n≤10, TbSin clusters are not encapsulated structures. In this work, the stability of clusters was predicted by calculating TbSin clusters’ dissociation energy and Sin clusters’ dissociation energy. It is easier to dissociate Tb atom from TbSin clusters than dissociating Si atom from TbSin clusters or Sin clusters. Among TbSin clusters (n=1-10), TbSi2is the most stable clusters, while TbSi7is the most unstable clusters. Si3is the most stable clusters, while Si8is the most unstable clusters, among Sin clusters (n=2-10).