Dynamical disorder and resonance energy transfer: a novel quantum-classical approach.

Resonance energy transfer (RET), at the heart of photosynthesis, supports life on earth, but also guarantees the operation of several technological devices, like organic light-emitting diodes and solar cells. Medium properties and dynamics largely affect RET efficiency, but reliable models addressing how molecular electron-vibration motion and solvent dynamics jointly affect RET are still missing. Here we propose a novel quantum-classical approach to describe RET in a non-adiabatic molecular system embedded in a dynamic polar environment. The approach, validated against optical properties of a dye in solution, is then applied to a RET-pair, demonstrating that dynamic disorder, as induced by a liquid polar solvent, boosts RET efficiency.