We report the formation of a series of metal-containing hydrogenated silicon clusters using an ion trap. Mass analyses reveal that many types of transition metal ions ( , Ta, W, Re, Ir, etc.) react with silane to form dehydrogenated cluster ions ( , 13, 12, 11, 9, respectively) as an end product, indicating that the metal atom is endohedral and stabilizes the Si polyhedral cage. This finding is confirmed by our ab initio calculation that is a W-encapsulating cage cluster, and is very stable owing to both the electronic and the geometrical shell closures.
- Received 5 September 2000
©2001 American Physical Society