Song Ning, Ying Ting-Ting, Tan Yu-Hui, Tang Yun-Zhi, Liao Juan, Wang Li-Juan, Wang Fang-Xin, Wan Ming-Yang
Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry, Faculty of Materials, Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou 341000, China.
Dalton Trans. 2023 Aug 15;52(32):11196-11202. doi: 10.1039/d3dt01426f.
Ferroelectric materials are not only important electronic functional materials, but also considered as the most promising intelligent basic materials, because they show good application prospects. Therefore, it is an urgent task to develop and explore new ferroelectric material systems. In addition, the most important feature of crown ethers is their ability to complex with positive ions, which is extremely useful in synthesis. We report that NHCHCl(18-crown-6) (1) has a phase transition temperature = 255 K, and there is an obvious SHG switch below . At the same time, the saturation polarization value = 1.25 μC cm is obtained from the hysteresis loop, which directly proves the ferroelectric nature of compound 1. It is noteworthy that the second harmonic response test of compound 1 shows a symmetric transition from a non-centrosymmetric to a centrosymmetric point group, that is a symmetry break from the paraelectric phase to the ferroelectric phase. This work is expected to promote the further exploration of organic crown ether ferroelectrics and provide a way to design and synthesize organic crown ether ferroelectrics.
铁电材料不仅是重要的电子功能材料，还被视为最具前景的智能基础材料，因为它们展现出良好的应用前景。因此，开发和探索新型铁电材料体系是一项紧迫任务。此外，冠醚最重要的特性是其与正离子络合的能力，这在合成中极为有用。我们报道NHCHCl(18 - 冠 - 6) (1)具有相变温度 = 255 K，且在此温度以下存在明显的二次谐波产生（SHG）开关效应。同时，从磁滞回线获得饱和极化值 = 1.25 μC cm，这直接证明了化合物1的铁电性质。值得注意的是，化合物1的二次谐波响应测试显示从非中心对称到中心对称点群的对称转变，即从顺电相到铁电相的对称性破缺。这项工作有望推动对有机冠醚铁电体的进一步探索，并为有机冠醚铁电体的设计与合成提供一条途径。
