密度泛函理论研究BeSin(n=1-12)团簇的结构、稳定性与电子性质

运用密度泛函理论(DFT),考虑多种初始构型下的自旋多重态,在B3LYP/6-311G基组水平上研究BeSi_n(n=1-12)团簇的平衡几何结构、电子性质、振动光谱与极化率.结果表明:BeSi_n团簇在基态附近有许多能量非常接近的同分异构体,且BeSi_n团簇的基态结构绝大多数为立体结构.n=1时,体系的基态为自旋三重态,n≥2时,则为单重态.铍原子的掺入使得主团簇的电子性质发生了明显的变化,掺杂使得体系的化学稳定性降低.BeSi₃,BeSi₅,BeSi₇与BeSi₉是幻数结构.团簇中原子间的成键相互作用随n的增大而增强.

Density Functional Theory Study of Geometry,Stability and Electronic Properties of BeSin(n=1-12) Clusters

Geometrical structures, stability, electronic properties, vibrational spectrum and polarizations of BeSi_n(n=1-12) clusters are investigated with density functional theory (DFT) at B3LYP/6-311G level. It indicates that there are many isomers with extremely close energies near the ground state. The most stable structures of BeSi_n clusters favor three-dimensional structures as n≥4. At n=1 spin multiplicity of the ground state structure of BeSi_n cluster is triplet while it is singlet as n≥2. Electronic properties of host clusters change obviously due to encapsulation of Be atom. Doping of Be atom reduce chemical stability of pure Si clusters, n=3, 5, 7 and 9 are magic numbers.