Near-room-temperature dielectric switch and thermal expansion anomaly in a new hybrid crystal: (Me2NH2)[CsFe(CN)(5)(NO)]

A new hybrid crystal, (Me2NH2)[CsFe(CN)(5)(NO)], featuring a double-layered nitroprusside-based inorganic framework with cubic-like cages encapsulating organic cations, undergoes a near-room-temperature phase transition accompanied by a dielectric switch and thermal expansion anomaly. The hidden mechanism was disclosed to be highly associated with order-disorder transition of organic cations and deformation of the inorganic framework.