由塑性相位过渡引起的分子铁电极化方向最相等
Heng-Yun Ye1, Jia-Zhen Ge1, Yuan-Yuan Tang1
1Ordered Matter Science Research Center, Southeast University , Nanjing 211189, People's Republic of China.
Journal of the American Chemical Society
|September 30, 2016
概括
研究人员发现了一种新型的分子离子铁电材料, 这种材料具有12个等效的铁电轴,是最著名的,可用于优质的多晶铁电轴.
科学领域:
- 材料科学
- 固态物理
- 晶体学
背景情况:
- 铁电材料在各种应用中至关重要,通常用作多晶陶.
- 具有多个等价极化方向的多轴铁电是多晶应用的首选.
- 现有的陶铁电材料,如BaTiO3,通常有三个或更少的等价铁电轴.
研究的目的:
- 引入一种具有前所未有的等价铁电轴数量的新型分子电离材料.
- 探索这种材料在制造先进的多晶体铁电陶方面的潜力.
主要方法:
- 四甲基酸盐的合成和表征.
- 研究其晶体结构和相位过渡.
- 对其多晶体形式的铁电性质的评估.
主要成果:
- 甲被确定为具有12个等效铁电轴的分子离子铁电,超过所有已知的铁电轴.
- 轴数之多归因于形成高度对称的立方晶体系统的塑性相位过渡.
- 该材料证明了在多晶膜中实现完美的宏观铁电性的能力.
结论:
- 甲代表了多轴铁电材料的重大进步.
- 它具有12个等价轴的独特结构,为设计高性能多晶体铁电陶提供了新的可能性.
- 这一发现为针对多晶体应用的新型多轴铁电结构铺平了道路.
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