Probing the electronic and structural properties of doped aluminum clusters: MAl₁₂^- (M=Li, Cu, and Au)

Authors

R. Pal, University of Nebraska-Lincoln
Li-Feng Cui, Washington State University, Richland
Satya S. Bulusu, University of Nebraska-LincolnFollow
Hua-Jin Zhai, Washington State University, Richland
Lai-Sheng Wang, Washington State University, Richland
Xiao Cheng Zeng, University of Nebraska-LincolnFollow

Date of this Version

1-10-2008

Comments

Published by American Institute of Physics. J. Chem. Physics 128, 024305 2008. ©2008 American Institute of Physics. Permission to use. http://jcp.aip.org/.

Abstract

Photoelectron spectroscopy (PES) is combined with theoretical calculations to investigate the electronic and atomic structures of three doped aluminum clusters, MAl₁₂^- (M=Li, Cu, and Au). Well-resolved PES spectra have been obtained at two detachment photon energies, 266 nm (4.661 eV) and 193 nm (6.424 eV). Basin-hopping global optimization method in combination with density-functional theory calculations has been used for the structural searches. Good agreement between the measured PES spectra and theoretical simulations helps to identify the global minimum structures. It is found that LiAl₁₂^- (C_5v) can be viewed as replacing a surface Al atom by Li on an icosahedral Al₁₃^-, whereas Cu prefers the central site to form the encapsulated D_3d^-Cu@Al₁₂^-. For AuAl₁₂^-(C₁), Au also prefers the central site, but severely distorts the Al₁₂^- cage due to its large size.