Stabilization of Si60 cage structure -: art. no. 135503

A comprehensive search for the stable geometries of bare Si-60 and Si-60 supported on a C-60 fullerene was carried out using first principles calculations based on density functional theory. In contrast to previous theoretical studies and in agreement with recent experiments, we show that Si-60 and C-60@Si-60 clusters are unstable in the fullerenelike cage structure. However, Si-60 cage can be stabilized by including within it, as endohedral units, small magic clusters such as Al12X (X = Si, Ge, Sn, Pb) and Ba@Si-20.