The Production of the Cluster Ions （NH₃）₂H₂⁺ and the ab initio Calculation of Their Structures

The ammonia clusters were studied using the technologies of the laser MPI MS and the molecular beam, and cluster ions （NH₃）₂H₂⁺ （1≤n≤6） wer measured obviously. The first evidence of existence of the cluster ions with n ＜4 experimently was given. We calculated the structures of the cluster ions using GAUSSIAN-94 package, and found stable structures for both ion NH₅⁺ and （NH₃）₂H⁺. We also compared our computational results with the related results repoted in the literatures, and pointed that the sturctrue we found is the only stable structures of this kind of cluster ions.