Stability and isomerization reactions of phenyl cation C6H5+ isomers

Abstract As a key polyatomic molecular cation that plays a pivotal role in growth of the polycyclic aromatic hydrocarbons, phenyl cation C 6 H 5 + exhibits various isomers and isomerization reactions. Investigation on the structure and stability of the isomers as well as the isomerization is important for better understanding the chemical reactions involving C 6 H 5 + cations. In this work, we have performed a theoretical study on the stability and isomerization reactions of C 6 H 5 + isomers at density functional theory B3LYP/6-311G (d, p) level. We have obtained a total of 60 isomers of C 6 H 5 + cations, most of which are reported for the first time. The geometries, vibrational frequencies, thermodynamic properties and stability of 28 out of 60 isomers have been summarized in detail. Different ring-to-ring and ring-to-chain isomerization pathways, which are connected via 28 transition states, have been investigated using the intrinsic reaction coordinate method. The results show that the isomerization reactions occur via hydrogen migration followed by bond-breaking and reconstruction.