Molecular Ferroelectric Piperidine-4-ylmethanaminium Perchlorate with Superior Switchable Dielectric Properties

A new piperidyl-based molecular ferroelectric piperidine-4-ylmethanaminium perchlorate (compound 1) has been successfully synthesized, which undergoes a reversible phase transition around T-c = 258.8 K. The spontaneous polarization of compound 1 is about 0.63 mu C/cm(2) and coercive field as small as 1.14 kV/cm at 192 K. The variable-temperature single-crystal X-ray diffraction reveals that the space group transforms from a polar space group of P2(1) at 173 K to a centrosymmetric space group of P2(1)2(1)2(1) at 293 K. Especially, the dielectric anomaly at the phase transition temperature increases more than 4 times, which indicates potential applications in switchable dielectric devices.