Key points are not available for this paper at this time.
The temperature dependence of magnetic susceptibility of Fe III (azp)(qsal-Me)·0.5CH 3 OH Hqsal-Me = 5-methyl- N -(8-quinoyl)salicylaldimine, H 2 azp = 2,2′-azobisphenol demonstrated that the spin-crossover (SCO) transition behavior changed from an abrupt transition to consecutive gradual conversions, and moreover, the initial abrupt transition was recovered, keeping the complex at room temperature. The variable-temperature crystal structures revealed that an SCO-triggered linkage isomerization of the azobenzene ligand from one orientation to two disordered orientations and the relaxation from the disordered orientations to the original orientation occurred. The high-spin to low-spin relaxation kinetics and theoretical calculation indicate that the pedal-like motion of the azobenzene ligand can be on in the high-spin state whereas off in the low-spin state.
Miyawaki et al. (2021) studied this question.