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Bistable switches (electrical switching between "ON" and "OFF" bistable states) have gradually developed into an ideal category of highly intelligent materials, due to their significant applications in optical technology, signal processors, data storage and other switchable media applications in the field of electrical devices. Here, we successfully designed and synthesized [(FC6H4C2H4NH3)2MCl4]n(FC6H4C2H4NH3+)=deprotonated 4‐fluoro‐ phenethylamine; M=Cd (1), Mn (2)), which realized the coupling of thermo‐dielectric switching characteristics, semi‐conductor characteristics and photo‐luminescent properties. DSC (differential scanning calorimetry) and dielectric measurements show that 1 is a sensitive dielectric bistable switch between the high dielectric (ON) and low dielectric (OFF) states. The temperature‐variable single crystal structure shows that the both 1 and 2 undergo a high‐temperature reversible phase transition around 383 K/380 K, which is caused by the order‐disordered transformation of organic cations and the slight distortion of the inorganic framework. In particular, 1 shows outstanding switchable dielectric behavior and semiconducting properties. Further, 1 and 2 emit strong green and yellow luminescence at 527 and 595 nm, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Although great progress has been made for H‐bonds type molecular ferroelectrics, the systems accompanying with chiral to chiral phase transitions are still very spare. Here we display a new hydrogen bond type molecular ferroelectric, the salt of 1‐(1‐naphthyl) ethylammonium‐nopinate, 1, which undergoes a paraelectric–ferroelectric phase transition around 202 K from one chiral point group (P212121) to another chiral point group (P21). The electric hysteresis loop under 100 K directly indicates it is a potential ferroelectric material with maximum spontaneous polarization (Ps) 2.3 uC/cm2. X‐ray single crystal diffraction analysis shows that the significant hydrogen bond change along the b‐axis direction results net dipole moment and leads to the spontaneous polarization. The exceptional dielectric response in the vicinity of 202 K exhibits remarkable dielectric anomalies along the b‐axis direction than the other two directions. The strong SHG (second harmonic generation) signal (‐1.31) without obvious changes dependence on temperature further confirm the chiral to chiral structural phase transition. [ABSTRACT FROM AUTHOR]