Collective behavior in the kinetics and equilibrium of solid-state photoreaction

There is current interest in developing photoactive materials that deform on illumination. The strategy to develop new molecules solution, and then incorporate these the solid-state either by crystallization or inserting them into polymers. This letter shows kinetics nature of photo-induced phase transitions are profoundly different single (solution) solid state using a lattice spin model. In where act independently, photoreaction follows first-order kinetics. However, interact with each other therefore behave collectively during reaction, photoreactions follow sigmoidal nucleation growth as transition. Further, we find exact strain has critical effect kinetics, equilibrium, microstructure formation. These predictions agree qualitatively experimental observations, provide insights for development materials.