Thermal and protonation-induced electron transfer coupled spin transition in a discrete [Fe 2 Co 3 ] Prussian blue analogue.

Multi-stimuli responsive switchable molecules have garnered interest for their potential applications in the field of magnetic materials. However, the persistent challenge lies in isolating these properties within the same material. Herein, we report a discrete [Fe 2 Co 3 ] pentanuclear cyanide bridged complex, [Co(L) 2 ] 3 [Fe(CN) 6 ] 2 ·20H 2 O, (1) (L = ( Z )- N '-(4-(trifluoromethyl)phenyl)picolinimidamide) which undergoes electron transfer coupled spin transition (ETCST) from [FeII2CoIIHSCoIII2] to [FeIII2CoII3] configurations through thermal activation and upon protonation.