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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
在一个可能的基于分子的多铁体中,室温以上的磁电合:三乙基甲基四博酸 (III)
Hong-Ling Cai1, Yi Zhang, Da-Wei Fu
1Ordered Matter Science Research Center, Southeast University, Nanjing, PR China.
Journal of the American Chemical Society
|October 31, 2012
概括
一种新型的分子多铁材料,三乙基甲基四博酸 (III),表现出室温以上的铁电和磁过渡. 这导致了显著的磁电合,这是先进电子应用的关键特性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 化学 化学 化学
背景情况:
- 具有同时呈现铁电和磁性排序的多铁材料对新型电子设备具有很大的兴趣.
- 发现接近室温的相变材料对于实际应用至关重要.
- 分子多铁在鱼性和加工方面具有潜在的优势.
研究的目的:
- 报告发现了一种新的分子多铁素材料.
- 为了研究三乙基甲基四博酸的铁电和磁性特性.
- 为了描述材料中的磁电介质合和相变.
主要方法:
- 三乙基甲基四博酸盐的合成和表征 (III).
- 温度依赖的介电和磁性测量.
- 分析相位过渡行为和磁磁电响应.
主要成果:
- 发现了一个潜在的室温以上的分子多铁素,三乙基甲基四博酸 (III) (1),被发现.
- 铁电和磁相转换发生在360K附近,显示出强大的磁电离合 (18%在0.6MHz).
- 在171K的低温铁电 - 铁电过渡与微小的磁性和介电异常被观察到.
结论:
- 三乙基甲基四博酸 (Triethylmethylammonium tetrabromoferrate) 是一个有前途的候选人,用于在室温以上的分子多铁素.
- 在室温附近的强磁电合凸显了其在传感器和内存设备中的应用潜力.
- 该材料复杂的相变行为需要进一步调查.
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To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
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