Photoinduced magnetic pole inversion in a ferro–ferrimagnet: (Fe0.40IIMn0.60II)1.5CrIII(CN)6

We tried to design the magnet exhibiting magnetic pole (N and S) inversion by photostimuli. The magnetization of ${\mathrm{Fe}}_{\mathrm{1.5}}^{\mathrm{II}}{\mathrm{Cr}}^{\mathrm{III}}{\mathrm{(CN)}}_{\mathrm{6}}\mathrm{\cdot 7.5H}{}_{\mathrm{2}}\mathrm{O}$ was changed in a photon mode by visible light. A ferro-ferrimagnet ${\mathrm{(Fe}}_{\mathrm{0.40}}^{\mathrm{II}}{\mathrm{Mn}}_{\mathrm{0.60}}^{\mathrm{II}}{\mathrm{)}}_{\mathrm{1.5}}{\mathrm{Cr}}^{\mathrm{III}}{\mathrm{(CN)}}_{\mathrm{6}}{\mathrm{\cdot 7.5H}}_{\mathrm{2}}\mathrm{O}$ mixed by ferromagnetic (Fe–Cr system showing the change of magnetization by optical stimuli) site and ferrimagnetic (Mn–Cr system showing no optical response) site showed negative magnetization at the temperature lower than compensation temperature ${\mathrm{(T}}_{\mathrm{comp}}$ =19 K). In this mixed metal cyanide magnet we have succeeded in demonstrating a novel magnetic behavior “photoinduced magnetic pole inversion.” Moreover, the magnetic pole inversion can be induced repeatedly by alternate optical and thermal stimulations.