极性晶体使用分子性:伪对称晶体向极化切换材料
Shinji Kanegawa1,2, Shu-Qi Wu1,2, Ziqi Zhou1
1Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan.
Journal of the American Chemical Society
|April 11, 2024
概括
研究人员开发了一种新方法来合成可切换的极化晶体, 这种策略可以控制先进电子设备中的温度依赖的偏振切换.
科学领域:
- 材料科学
- 晶体学
- 化学学
背景情况:
- 具有可切换偏振的极性化合物对于铁电记忆器和火电传感器等设备至关重要.
- 缺乏合成这种极性化合物的总体策略, 阻碍了它们的广泛应用.
- 现有的中心对称结构往往取消双极时刻,防止所需的极性质.
研究的目的:
- 建立一个合理的合成策略,以创建可切换的极化晶体.
- 研究新型极性CoGa和CoZn晶体的合成和特性.
- 以示控制温度依赖的偏振切换使用奇拉连接体.
主要方法:
- 通过使用特定的性配体 (SS-cth和RR-cth) 将Co复合体替换为Ga复合体,合成极性CoGa晶体.
- 使用与RR-cth和与SS-cth的Ga复合物的对应性复合物来实现极性.
- 通过温度依赖的电二极矩变化的分析来研究极化切换现象.
主要成果:
- 成功合成了极性CoGa晶体,在伪极性 (低温) 和极性 (高温) 状态之间呈现极化切换.
- 开发了一种可偏离切换的CoZn复合体,其温度依赖性相反 (在低温时极性,在高温时伪非极性).
- 证明 Co 复合体中的金属-合体电荷转移是观察到的极化变化的原因.
结论:
- 已经建立了使用奇拉联体合成极性晶体的设计策略.
- 开发的方法允许精确控制温度依赖的偏振切换.
- 这种方法为先进的电子应用提供了一种新方法,与传统的铁电材料形成鲜明对比.
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