Wang Qing, Liu Qing, Xie Yongfa, Wei Zhenhong, Cai Hu
College of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China.
Inorg Chem. 2025 Apr 21;64(15):7630-7638. doi: 10.1021/acs.inorgchem.5c00640. Epub 2025 Apr 9.
Molecular ferroelectrics have garnered significant attention owing to their environmental compatibility, facile synthesis, lightweight nature, and structural versatility. In this study, we present a novel one-dimensional (1D) organic-inorganic hybrid perovskite molecular ferroelectric, [(NMe)PCHCl]PbI (), which undergoes two successive reversible phase transitions. This compound demonstrates distinct spontaneous polarization in ferroelectric domains, along with two-step switching in second-harmonic generation (SHG) and dielectric responses. Variable-temperature single-crystal X-ray diffraction reveals a symmetry-breaking transition in , shifting from the centrosymmetric 6/ space group to the polar noncentrosymmetric 6 ferroelectric phase. This transition is primarily driven by an order-disorder transformation of the [(NMe)PCHCl] cation. Furthermore, compound exhibits promising semiconductor characteristic with a bandgap of 2.70 eV. This material's unique high-low-off SHG-switching behavior and robust polarization switching ( = 0.3 μC·cm) position it as a multifunctional platform for next-generation applications in multistate memory devices, programmable optical modulators, and temperature-responsive sensors, addressing critical limitations of conventional molecular ferroelectrics in stability and functional diversity.
分子铁电体因其环境兼容性、易于合成、重量轻和结构多样性而备受关注。在本研究中，我们展示了一种新型的一维（1D）有机-无机杂化钙钛矿分子铁电体，[(NMe)PCHCl]PbI（），它经历了两个连续的可逆相变。该化合物在铁电畴中表现出明显的自发极化，以及二次谐波产生（SHG）和介电响应的两步切换。变温单晶X射线衍射揭示了中的对称破缺转变，从中心对称的6/空间群转变为极性非中心对称的6铁电相。这种转变主要由[(NMe)PCHCl]阳离子的有序-无序转变驱动。此外，化合物表现出有前景的半导体特性，带隙为2.70 eV。这种材料独特的高-低-关断SHG切换行为和强大的极化切换（= 0.3 μC·cm）使其成为多态存储器件、可编程光调制器和温度响应传感器等下一代应用的多功能平台，解决了传统分子铁电体在稳定性和功能多样性方面的关键限制。
