Pb12 2-: plumbaspherene.
Although Si or Ge is not known to form empty cage clusters such as the fullerenes, we recently found a unique 12-atom icosahedral tin cluster, Sn12 2- (stannaspherene). Here we report photoelectron spectroscopy and theoretical evidence that Pb12 2- is also a highly stable icosahedral cage cluster and bonded by four delocalized radial pi bonds and nine delocalized on-sphere sigma bonds from the 6p orbitals of the Pb atoms. Following Sn12 2-, we coin a name, plumbaspherene, for the highly stable and nearly spherical Pb12 2- cluster, which is expected to be stable in solution and the solid state. Plumbaspherene has a diameter of approximately 6.3 A with an empty interior volume large enough to host most transition metal atoms, affording a new class of endohedral clusters.
Cui
Li-Feng
LF
Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99354, USA.
Huang
Xin
X
Wang
Lei-Ming
LM
Li
Jun
J
Wang
Lai-Sheng
LS