化盐中的质子动力学和室温铁电与质子海绵
Sachio Horiuchi1, Reiji Kumai, Yusuke Tokunaga
1Correlated Electron Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8562, Japan. s-horiuchi@aist.go.jp
Journal of the American Chemical Society
|September 11, 2008
概括
铁电和质子转移动力学是通过使用2,3,5,6-四2'-二) (TPPZ) 和酸实现的. 这项研究揭示了新型晶体结构中的相位过渡和室温铁电.
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:
- 铁电材料对于电子设备至关重要.
- 质子转移动力学在材料性质中起着关键作用.
- 设计具有可调节性质的新型铁电器仍然是一个挑战.
研究的目的:
- 在新材料中研究铁电和质子转移动态.
- 探索TPPZ-酸盐中的结构性质关系.
- 了解铁电相变的机制.
主要方法:
- 介电测量以确定相位过渡.
- 同步射线X射线衍射用于研究晶体结构和质子动态.
- 化研究以证实质子参与.
主要成果:
- 在334 K (Hba) 和172 K (Hca) 观察到的相变.
- 室温铁电的证据是极化逆转和火电.
- 在分子内N-H-N键和循环二次体中确定了质子动态.
- 无序的二次体在T (c) 以上呈现双质子转移,在铁电相中排序.
- TPPZ滴定作为一个质子海绵,与质子定位驱动铁电.
结论:
- TPPZ和酸的组合产生具有特征性质子转移动态的铁电材料.
- 质子的排序和定位在TPPZ分离和酸二次体内,是观察到的铁电的原因.
- 这些发现提供了对新型基于质子的铁电材料设计的见解.
相关概念视频
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