Calculation of Geometric, Thermodynamic and Activation Parameters of the Reaction of Interaction of Fullerene C60 With Cyclopentadiene by the B3lyp Method Taking Into Account Dispersion Interactions

In this work, the interaction reaction between cyclopentadiene and fullerene C60 was investigated at the B3LYP/def2-TZVP level. Since this reaction produces a prereaction van der Waals complex, in the formation of which dispersion interactions play an important role, the influence of these interactions on the structural and energy characteristics of all systems was studied in the framework of various semi-empirical Grimme models. The geometrical characteristics of the reactants, product, transition state, and van der Waals complex are analyzed, and it is found that taking into account dispersion interactions has a significant effect only on the structure of the van der Waals complex, while in other cases the differences are minimal. The obtained values of the activation enthalpy of the direct (6.6 kcal/mol) and reverse (21.1 kcal/mol) reactions, as well as the enthalpies of the entire process (-14.5 kcal/mol), obtained using B3LYP/def2-TZVP D4, are in good agreement with the experimental values (6.9 kcal/mol, 26.7±2.2 kcal/mol and -19.8±2.2 kcal/mol, respectively).