Au5~25 Pd团簇结构与性质的理论研究  

A theoretical study on structures and properties of Au5~25 Pd clusters

作　　者：伍建君 汪严 唐小琴[1] 夏星[1] 孙国峰[1] 唐典勇[1] 

机构地区：[1]乐山师范学院化学学院,四川乐山614000

出　　处：《化学研究与应用》2014年第8期1225-1231,共7页Chemical Research and Application

基　　金：国家大学生创新创业训练计划项目(项目编号:201210649002)资助

摘　　要：用basin-hopping算法结合密度泛函PBE方法系统搜索了Au5-25 Pd团簇的全局稳定结构,并对团簇几何结构,稳定性,Fermi能级,化学硬度和前线轨道进行了分析。计算结果表明,Au5 Pd,Au7 Pd和Au11 Pd团簇为平面结构,其他团簇均为立体结构,与相同原子数纯金团簇结构类似。所有团簇中,Pd原子均位于配位数较高位置。团簇平均结合能随金原子数增大而逐渐增大,并有收敛到某点的趋势。偶数金原子团簇较相邻的奇数金原子团簇稳定。团簇的Fermi能级随团簇增大呈奇偶振荡,偶数金原子团簇的Fermi能级较相邻奇数金原子团簇的低,与金团簇Fermi能级变化类似。 Au7 Pd,Au12 Pd,Au16 Pd和Au18 Pd团簇化学活性较高。 Au5-19 Pd团簇中Pd原子优先与CO,烯烃,炔烃等分子形成配位键。 CO等小分子仍然吸附到Au20-25 Pd团簇的顶点或面中心的金原子。The global minima of Au5~25 Pd clusters were systematically searched by means of the basin-hopping algorithm in combi-nation with PBE functional of density functional theory. The structure,relative stability,Fermi level,chemical hardness,and frontier molecular orbitals of these clusters were investigated at the PBE/DND level. The computational results indicated that Au5 Pd, Au7 Pd,and Au11 Pd clusters were planar structures;the other clusters were three-dimensional structures. The structures of Pd-doped gold clusters were similar with the same-sized gold clusters. The average binding energies and Fermi levels were similar to those of the pure gold clusters,demonstrating an odd-even oscillation. The chemical activities of Au7 Pd,Au12 Pd,Au16 Pd,and Au18 Pd clus-ters were larger than those of the others. The small molecules（ such as CO,alkyne,alkene et al） were preferred to adsorb on the Pd atom of Au5~19 Pd clusters,while they were adsorbed on the surface gold atom of Au20~25 Pd clusters.

关 键 词：Basin-hopping算法 金钯团簇 相对论效应 Fermi能级 前线轨道 

分 类 号：O643.12[理学—物理化学]