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Updated: May 26, 2026

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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
铁电和压力诱导的现象是由酸超分子的中性离子价值不稳定性驱动的
Reiji Kumai1, Sachio Horiuchi, Jun Fujioka
1Condensed Matter Research Center (CMRC) and Photon Factory, High Energy Accelerator Research Organization (KEK), Institute of Materials Structure Science, Tsukuba, 305-0801, Japan. reiji.kumai@kek.jp
Journal of the American Chemical Society
|December 7, 2011
概括
费纳与酸的铁电共晶体显示结构变化和质子转移. 压力和温度显示出普遍的相位图,由价值不稳定性和库伦相互作用驱动.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 超分子铁电共晶体通过结构转换提供可调节的特性.
- 了解质子转移机制是设计新型电子材料的关键.
研究的目的:
- 研究氨酸 (Phz) 联合晶体与氨酸 (H(2) ca),氨酸 (H(2) ba) 和氨酸 (H(2) fa) 的结构转化和固态酸反应.
- 阐明压力-温度相位图和这些系统中铁电的起源.
主要方法:
- 取决于温度的介电电容度测量.
- 同步射线X射线衍射研究.
- 分析质子转移和结构相变的分析.
主要成果:
- 同晶体表现出不完全的质子位移,形成低于基里点的半离子状态.
- 在Phz-H(2) fa共晶体中的铁电是由水静压 (~0.6 GPa) 诱导的.
- 连续的相位过渡到不相称和相称调制相位发生在较低的温度.
- 建立了一个通用的压力-温度相位图,显示在环境压力下不同的基本状态.
结论:
- 结构转换和质子转移之间的相互作用决定了铁电的行为.
- 价值不稳定性和挫败的库伦相互作用导致电荷不成比例和独特的空间排序.
- 这些发现提供了对先进铁电材料设计的见解.
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