Dissociation pathways of cyclohexane trication

Density functional B3LYP and ab initio G3(MP2,CCSD)//B3LYP calculations have been performed to study isomerization and dissociation pathways of C 6 H 12 3 + in relation to the Coulomb explosion mechanism of cyclohexane. Cyclohexane trication is found to be metastable kinetically as the highest barrier on its decomposition pathway corresponding to the 2,1-H shift in the initial open-chain intermediate formed spontaneously after multiphoton ionization of cyclohexane is only 3.0 kcal/mol. The most favorable dissociation channels lead to the C 4 H 8 2 + + C 2 H 4 + , C 5 H 9 2 + + CH 3 + , and C 3 H 6 2 + + C 3 H 6 + products and all of them share the same reaction step with the highest barrier.