Large Spontaneous Polarization Ferroelectric Property, Switchable Second-Harmonic Generation Responses, and Magnetism in an Fe-Based Compound

Since the switchable spontaneous polarization of ferroelectric materials endows it with many useful properties such as a large pyroelectric coefficient, switchable spontaneous polarization, and semiconductor, it has a wide range of application prospects, and the research of high-performance molecular ferroelectric materials has become a hot spot. We obtained a 0D organic–inorganic hybrid ferroelectric [(CH 3 ) 3 NCH 2 CH 2 CH 3 ] 2 FeCl 4 ( 1 ) with well-defined ferroelectric domains and excellent domain inversion and exhibited a relatively large spontaneous polarization ( P s = 9 μC/m –2 ) and a Curie temperature ( T c ) of 394 K. Furthermore, compound 1 belongs to the non-centrosymmetrical space group Cmc 2 1 and has a strong second-harmonic generation signal. Interestingly, we also performed magnetic tests on 1, which confirmed that it is a magnetic material. This work provides clues for exploring the application of high-performance molecular ferroelectric materials in future multifunctional smart devices.