Bulusu Satya, Zeng X C
Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, USA.
J Chem Phys. 2006 Oct 21;125(15):154303. doi: 10.1063/1.2352755.
We performed a global-minimum search for low-lying neutral clusters (Au(n)) in the size range of n=15-19 by means of basin-hopping method coupled with density functional theory calculation. Leading candidates for the lowest-energy clusters are identified, including four for Au(15), two for Au(16), three for Au(17), five for Au(18), and one for Au(19). For Au(15) and Au(16) we find that the shell-like flat-cage structures dominate the population of low-lying clusters, while for Au(17) and Au(18) spherical-like hollow-cage structures dominate the low-lying population. The transition from flat-cage to hollow-cage structure is at Au(17) for neutral gold clusters, in contrast to the anion counterparts for which the structural transition is at Au(16) (-) [S. Bulusu et al., Proc. Natl. Acad. Sci. U.S.A. 103, 8362 (2006)]. Moreover, the structural transition from hollow-cage to pyramidal structure occurs at Au(19). The lowest-energy hollow-cage structure of Au(17) (with C(2v) point-group symmetry) shows distinct stability, either in neutral or in anionic form. The distinct stability of the hollow-cage Au(17) calls for the possibility of synthesizing highly stable core/shell bimetallic clusters M@Au(17) (M=group I metal elements).
我们采用盆地跳跃法结合密度泛函理论计算,对尺寸范围为(n = 15 - 19)的低能中性团簇((Au(n)))进行了全局最小搜索。确定了能量最低团簇的主要候选结构,包括(Au(15))的四种、(Au(16))的两种、(Au(17))的三种、(Au(18))的五种以及(Au(19))的一种。对于(Au(15))和(Au(16)),我们发现壳状扁平笼状结构在低能团簇中占主导,而对于(Au(17))和(Au(18)),球状空心笼状结构在低能团簇中占主导。中性金团簇从扁平笼状结构到空心笼状结构的转变发生在(Au(17)),这与阴离子团簇相反,阴离子团簇的结构转变发生在(Au(16)^-) [S. Bulusu等人,《美国国家科学院院刊》103, 8362 (2006)]。此外,从空心笼状结构到金字塔结构的转变发生在(Au(19))。(Au(17))的能量最低的空心笼状结构(具有(C_{2v})点群对称性)在中性或阴离子形式下都表现出明显的稳定性。空心笼状(Au(17))的明显稳定性表明合成高稳定性核/壳双金属团簇(M@Au(17))((M =)第一族金属元素)具有可能性。