Relaxation kinetics of photoexcited states in a chain of exchange clusters in the mean-field approximation

Abstract

A theoretical description of the relaxation kinetics of photoexcited states in chains of exchange clusters is developed in the mean-field approximation. It is found that in contrast to the analog of this phenomenon in the light-induced electron spin-state trapping (LIESST) effect well known for the conventional spin crossover compounds of Fe(II), the relaxation kinetics in chains of exchange clusters can be self-decelerating due to the different relaxation rates of two types of photoexcited states in the chain. The proposed theoretical approach qualitatively explains the experimentally observed difference in relaxation kinetics at different initial excitation intensities of the system during photoexcitation of breathing crystal compounds.