Home – Home – Jornals – Journal of Structural Chemistry 2012 number 2

According to the data of UB3LYP/6-31G* and UMP2/cc-pVTZ calculations, the adiabatic potential energy surface of the cyclopentane radical cation is very intricate and combines six types of stationary structures of C_s and C₂ symmetry. Ten equivalent C_s structures with the totally symmetric electronic state (C_s (²A′)) correspond to global minima. Conformational transitions between the global minima occur along the inversion and pseudorotation coordinates, for each pair of minima the conformational transition occurring in one stage (through the only transition state). The inversion barrier is ~2 kcal/mol; pseudorotation barriers are ~4-8 kcal/mol. The structure of the potential surface provides the interpretation of the EPR data as a result of dynamic averaging over 20 C_s (²A′) and C₂ (²A) stationary structures.