Modeling (Prediction) the Structure of Possible Transition States of Aromatic Hydrocarbones
Based on the conjugate p-electron system properties, a method is proposed for predicting possible spatial structures of aromatic hydrocarbons during their skeletal carbon transformation. The existence of the predicted spatial structures is caused by the stabilizing effect of the π-electron conjugation. The proposed method for predicting possible spatial structures was verified by DFT B3LYP/6-31G*, as well as by the RHF 6-31G basis, taking into account the electron correlation at the MR4-SDTQ on the example of benzene and hexafluorobenzene molecules. The stability of the results of the proposed method is shown regardless of the methods used for calculating the electronic structure of molecules. It is found that of all the predicted possible spatial structures, one corresponds to the ground state, and the others to transition States. Using the Gonzales-Schlegel method for finding potential barriers, schemes of thermal isomerization of benzene and hexafluorobenzene are constructed that correspond to experimental data.