A direct isomerization path for the H6+ cluster.: An ab initio molecular orbital study

We carried out ab initio molecular orbital calculations for the H6+ cluster and found two isomers of H6+ and the transition state (TS) for the direct isomerization. Analysis of the intrinsic reaction coordinate confirmed that the TS is located at the saddle point of the isomerization path. The existence of the direct isomerization path for H6+ may be one of the reasons for the observation of Kirchner and Bowers that the yield of H6+ is by far the largest among the even-membered Hn+ clusters produced.