Wang Lei-Ming, Pal Rhitankar, Huang Wei, Zeng Xiao Cheng, Wang Lai-Sheng
Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99354, USA.
J Chem Phys. 2009 Feb 7;130(5):051101. doi: 10.1063/1.3073884.
The golden Au(16)(-) cage is doped systematically with an external atom of different valence electrons: Ag, Zn, and In. The electronic and structural properties of the doped clusters, MAu(16)(-) (M = Ag,Zn,In), are investigated by photoelectron spectroscopy and theoretical calculations. It is observed that the characteristic spectral features of Au(16)(-), reflecting its near tetrahedral (T(d)) symmetry, are retained in the photoelectron spectra of MAu(16)(-), suggesting endohedral structures with little distortion from the parent Au(16)(-) cage for the doped clusters. Density functional calculations show that the endohedral structures of M@Au(16)(-) with T(d) symmetry are low-lying structures, which give simulated photoelectron spectra in good agreement with the experiment. It is found that the dopant atom does not significantly perturb the electronic and atomic structures of Au(16)(-), but simply donate its valence electrons to the parent Au(16)(-) cage, resulting in a closed-shell 18-electron system for Ag@Au(16)(-), a 19-electron system for Zn@Au(16)(-) with a large energy gap, and a 20-electron system for In@Au(16)(-). The current work shows that the electronic properties of the golden buckyball can be systematically tuned through doping.
通过用具有不同价电子的外部原子（Ag、Zn和In）对金色的Au(16)(-)笼进行系统掺杂。通过光电子能谱和理论计算研究了掺杂团簇MAu(16)(-)（M = Ag、Zn、In）的电子和结构性质。观察到，反映其近四面体（Td）对称性的Au(16)(-)的特征光谱特征在MAu(16)(-)的光电子能谱中得以保留，这表明掺杂团簇的内包结构与母体Au(16)(-)笼相比几乎没有变形。密度泛函计算表明，具有Td对称性的M@Au(16)(-)的内包结构是低能结构，其模拟的光电子能谱与实验结果吻合良好。研究发现，掺杂原子不会显著扰动Au(16)(-)的电子和原子结构，而是简单地将其价电子给予母体Au(16)(-)笼，从而使Ag@Au(16)(-)形成闭壳层18电子体系，Zn@Au(16)(-)形成具有大能量间隙的19电子体系，In@Au(16)(-)形成20电子体系。目前的工作表明，可以通过掺杂系统地调节金色巴基球的电子性质。
