The unimolecular reaction theory was founded and developed by Lindemann, Hinshelwood, Ramsperger-Kassel-Marcus (RRKM) theory, the vibrational degrees of freedom of reactants and transition states are typically treated quantum mechanically, while rotational and translational degrees of freedom are generally treated classically. Besides, it assumes that internal vibrational redistribution (IVR) is relatively fast and complete on the time scale of the unimolecular reaction. If IVR is slow, the initial rate coefficient will be microcanonical, while at later times this value will differ. The previous experimental results were aligned well with the RRKM predictions, indicating that CH3NC is a textbook RRKM molecule.