Optically induced switching in spin-crossover compounds: microscopic and macroscopic models and their relationship.

We present the examination of light induced behavior of spin-crossover compounds. We focus on the switching phenomena between low-spin and high-spin states of the system. The connection between the Ising-like model and the macroscopic evolution equation has been analyzed. By means of numerical simulations, we found the dynamical potential changes, the corresponding light induced hysteresis, and the transient regimes. The statistical properties of the system in contact with a heat bath are shown in a stationary probability distribution.