Thermodynamics of the elementary reactions for the internal base prFMN^im → prFMN^ket photoisomerization (Type (4) mechanism), obtained from the DFT/B3LYP/DZP, TD-DFT/B3LYP/DZP and TST methods. ΔG° and ΔH° = Gibbs free energy and enthalpy in kJ mol⁻¹; ΔS° = entropy in kJ mol⁻¹ K⁻¹; ΔG°^,Tot = total reaction Gibbs free energy for prFMN^im → prFMN^ket and; ΔS°^,Rx = reaction entropy of all the elementary processes; T = temperature in K.