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Updated: May 21, 2026

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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
铁电是由分子旋转器中的扭转运动的顺序引起的
Yi Zhang1, Wen Zhang, Shen-Hui Li
1Ordered Matter Science Research Center, Southeast University, Nanjing 211189, P. R. China.
Journal of the American Chemical Society
|June 13, 2012
概括
一种新的金属有机化合物在235K时表现出从平电到铁电的相变,由分子旋转器动力学驱动. 化研究证实质子排序不是铁电的原因.
科学领域:
- 无机化学 无机化学
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
背景情况:
- 金属有机化合物为先进的应用提供可调节的特性.
- 了解分子动力学对于设计功能性材料至关重要.
研究的目的:
- 为了合成和表征一种新型单核金属有机化合物, [Cu ((Hdabco)) ((H ((2) O)) Cl ((3) ].
- 为了研究它的电到铁电相位过渡和动态行为.
主要方法:
- 单晶X射线衍射的X射线衍射方法
- 热分析 (DSC/TGA) 的方法
- 介电和铁电测量方法
- 第二次波代 (SHG) 实验
- 固态核磁共振 (NMR) 光谱学
主要成果:
- 该化合物在235K (T(c)) 时呈现相变.
- 在室温以上,它可以作为一个分子旋转器,其中 (Hdabco) 部分在旋转.
- 在235-301 K之间观察到旋转器的扭转运动.
- 在T (c) 以下的铁电力归因于有序的分子排列和阴离子/离子位移.
结论:
- 合成的化合物表现出独特的平电到铁电切换行为.
- 分子转子动力学显著影响观察到的铁电性质.
- 质子排序不是铁电的起源,正如对化模拟物的研究所证明的那样.
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