ZPE-corrected gas-phase PES (in kJ mol⁻¹) of the interconversion between the anti and syn conformers of glycolamide, calculated at the BHLYP-D3(BJ)/ma-def2-TZVP (in red) and revDSD/junTZ (in blue) levels of theory. The dihedral angle Φ_OCCO, defining the syn and anti conformations and adopted as the reaction coordinate that drives the interconversion process, is also shown for the localized stationary points (in degrees). For each level of theory, the TS imaginary frequency (ω, in cm⁻¹) is also reported. For the TS, two different orientations are shown for the sake of clarity.