PRES 28

Sn₁₂^2-: Stannaspherene

Li-Feng Cui, lifeng.cui@pnl.gov¹, Xin Huang, xin.huang@pnl.gov¹, Lei-Ming Wang, leiming.wang@pnl.gov¹, Dmitry Yu. Zubarev, dzoubarev@cc.usu.edu², Alexander I Boldyrev, boldyrev@cc.usu.edu³, Jun Li, jun.li@pnl.gov⁴, and Lai-Sheng Wang, ls.wang@pnl.gov¹. (1) Department of Physics, Washington State University, 2710 University Drive, Richland, WA 99354, (2) Department of Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, UT 84322-0300, (3) Chemistry and Biochemistry, Utah State University, 0300 Old Main Hill, Logan, UT 84322, (4) W. R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, richland, WA 99352

During photoelectron spectroscopy experiments aimed at understanding the semiconductor-to-metal transition in tin clusters, the spectrum of Sn₁₂^- was observed to be remarkably simple and different from that of Ge₁₂^-, suggesting that Sn₁₂^- is a unique and highly symmetric cluster. It was found to possess a slightly distorted cage structure with C_5v symmetry. However, adding an electron to Sn₁₂^- resulted in an I_h-Sn₁₂^2- cluster, which was synthesized as K⁺[Sn₁₂^2-]. The I_h-Sn₁₂^2- cage is shown to be bonded by four delocalized radial π bonds and nine delocalized on-sphere tangential σ bonds from the 5p orbitals of the Sn atoms, whereas the 5s² electrons remain largely localized and nonbonding. The bonding pattern in Sn₁₂^2- is similar to the well-known B₁₂H₁₂^2- cage. The Sn₁₂^2- cage, for which a name “stannaspherene” is coined, has a diameter of 6.1 Å, suggesting it can trap a variety of atoms to form endohedral stannaspherenes.

SWNTs From Synthesis to Application, From the Lab to the Fab: In Memory of Dr. Richard Smalley
4:30 PM-6:30 PM, Sunday, 10 September 2006 Moscone Center -- Room 305, Poster

Presidential Event

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006