When coupling molecular vibration to the resonant cavity (solid lines), the populations of |ν R (blue) increase significantly compared to the cavity-free case (dashed lines). Note that the population of |ν R has a steady accumulation for both inside cavity (solid) and outside cavity (dash) situations, indicating a well-defined rate process. On the other hand, this enhancement of population growth is not very significant for higher-energy vibrational states, such as |ν 4 (dark gray) and |ν 5 (light gray), indicating their less important role in the VSC process at T = 300 K. When coupled to a resonant cavity (solid), the steady-state populations of |ν L and |ν R for the cavity-coupling case are slightly larger than the cavity-free case. In other words, the steady-state populations of those low-lying vibrational excited states are enhanced due to the presence of a cavity mode (and its associated loss described by a photon bath), when it is in resonance with the quantum vibration frequency ω 0 .