After filtering, full geometry optimization and vibrational frequency calculations were performed at ωB97X-D/6-31++G(d,p) level of theory. Structures where the lowest vibrational frequencies were negative and structures, which did not converge were resubmitted for further optimization. After all DFT calculations were finished, the quasi-harmonic approx-imation were applied using a frequency cut-off at 100 cm -1 . All frequencies below this cut-off are treated as free rotations when calculating the entropy. Finally, single-point electronic energies were calculated with the DLPNO-CCSD(T 0 ) method on the five structures lowest in Gibbs free energy. For these calculations, the RI-JK approximation with the aug-cc-pVTZbasis set, and with an auxiliary basis set for the Coulomb and exchange parts was applied together with the TightSCF convergence criterion.