Photoreversible spin-crossover ferrimagnetism in Fe2[Nb(CN) 8](4-methylpyridine) 8·2H2O

Abstract

A cyanido-bridged FeNb bimetal assembly, Fe2[Nb(CN) 8]- (4-methylpyridine)8·2H2O, was synthesized. This compound exhibits a two-step spin-crossover phenomenon between FeII high-spin (FeII HS, S = 2) and FeII low-spin (FeII LS, S = 0) at 112 and 95 K. Irradiation with 532-nm light converts the paramagnetic state to a ferrimagnetic state with a Curie temperature of 14K and a coercive field of 2300 Oe. Furthermore, irradiating with 785-nm light reduces magnetization due to the reverse photoinduced spin-crossover phenomenon.