Dehydration-actuated single-chain magnet through charge transfer in a cyanide-bridged Fe2Co chain

Abstract A cyanide-bridged Fe2Co 4,2-ribbon single-chain magnet, {[Fe(bipy)(CN)4]2[Co(phpy)2]} (1, bipy = 2,2-bipyridine; phpy = 4-phenylpyridine) was obtained by the dehydration of {[Fe(bipy)(CN)4]2[Co(phpy)2]}·2H2O (1·2H2O). The electron-transfer-coupled spin transition (ETCST) was achieved during the dehydration process from 1·2H2O to 1, with the electronic configurations transforming from {FeIILS(µ-CN)CoIIILS(µ-NC)FeIIILS} to {FeIIILS(µ-CN)CoIIHS(µ-NC)FeIIILS} (LS = low spin, HS = high spin). The magnetic characterization indicates that the dehydrated 1 exhibits the dehydration-actuated single-chain magnetic (SCM) behaviour.