The structures, conversions and fragmentations of C 2H 6O 2+ isomers: An ab initio study

Abstract

The fragmentations of a C 2H 6O dication in both singlet and triplet states are investigated in the present study. We propose several probable reaction channels to explain the source of the peaks which are found in the mass spectrum of ethanol under an intense laser field, but fail to reproduce it theoretically by considering only the fragmentation of a C 2H 6O radical cation. It is difficult for the C 2H 6O 2+ isomers in singlet state to undergo fragmentation, except for the H 2 elimination from ethanol dication, to generate CH 3COH 2+. However, the fragmentation can take place easily from the C 2H 6O 2+ isomers in triplet state. There exist low energy channels of the C 2H 6O dication in singlet state, to generate CH 3COH 2+, CH 4 + , CHOH +, CH 3 + , CHOH 2 + , CH 2 + , CH 2 OH 2 + , COH +, H +, CH 2 CHOH 2 + , CH 2CH + and H 3O +. However, with similar consideration, the low energy channels of OH +, CH 3 CH 2 + (T), CH 2 CH 2 + , H 2O +, CH 2O + and CH 2 OH 2 + , are available only in triplet state. The inter-conversions between any two C 2H 6O 2+ isomers in both singlet and triplet states are easier than their fragmentation reactions, except for CH 2 + and β-H eliminations from those dications in triplet state.