Resonant catalysis of thermally activated chemical reactions with vibrational polaritons

Interaction between light and matter results in new quantum states whose energetics can modify chemical kinetics. In the regime of ensemble vibrational strong coupling (VSC), a macroscopic number $$N$$ N of molecular transitions couple to each resonant cavity mode, yielding two hybrid light–matter (polariton) modes and a reservoir of $$N-1$$ N − 1 dark states whose chemical dynamics are essentially those of the bare molecules. This fact is seemingly in opposition to the recently reported modification of thermally activated ground electronic state reactions under VSC. Here we provide a VSC Marcus–Levich–Jortner electron transfer model that potentially addresses this paradox: although entropy favors the transit through dark-state channels, the chemical kinetics can be dictated by a few polaritonic channels with smaller activation energies. The effects of catalytic VSC are maximal at light–matter resonance, in agreement with experimental observations.