Collective effects in cavity-modified vibrational energy redistribution

While the emerging field of vibrational polariton chemistry has the potential to overcome traditional limitations of synthetic chemistry and energy transport and conversion, the underlying mechanism is not yet well understood. (For further details, see our perspective: “A Roadmap Toward the Theory of Vibrational Polariton Chemistry.”) We have already explored the dynamics of unimolecular dissociation reactions that are rate-limited by intramolecular vibrational energy redistribution (IVR) processes. Using a classical model of a bent triatomic molecule, where the two outer atoms are bound by anharmonic Morse potentials to the center atom, we showed that IVR can be modified inside an infrared cavity, either slowing down or accelerating depending on the conditions. An important question that we have not answered yet, however, is how IVR is impacted in the case of many molecules inside the cavity, a situation that is much more relevant to actual experiments. Studying many molecules will likely be a computational challenge, so on our way there, we will have to develop a deeper mechanistic understanding for why exactly coupling to the cavity changes IVR, thereby allowing us to simplify our model even further for more efficient computational scaling.