Laser ablation of Co/Ge mixtures: a new type of endohedral structure, a semiconductor cage trapping a metal atom

In experiments on Co/Ge binary clusters by laser vaporization, a remarkably strong signal in the mass spectrum was presented, which was assigned to the cluster anion consisting of ten germanium atoms and one cobalt atom, [CoGe 10 ] − . For this cluster anion we suggest an endohedral structure – a Ge 10 cage trapping a Co atom in its interior. Reactions between cobalt clusters and germanium clusters using a laser double ablation reactor also confirmed the endohedral structure. According to the electronic and geometrical shell closures, a bicapped tetragonal antiprism structure was predicted for this endohedral [CoGe 10 ] − cluster anion. Copyright © 2001 John Wiley & Sons, Ltd.