在单临床MAB铁电相中允许的域壁
1Department of Materials Science and Engineering, Tel Aviv University, Wolfson Building for Mechanical Engineering, Tel Aviv, 6997801, Israel.
Acta crystallographica. Section A, Foundations and advances
|December 7, 2023
概括
这项研究制定了矿氧化物中单临铁电域微结构的几何规律. 它确定了84个允许的域墙,增强了对这些复杂结构的理解,用于材料科学应用.
科学领域:
- 晶体学和材料科学 材料科学
- 固体物理和铁电力学
背景情况:
- 单临铁电相对于理解铁电材料,特别是矿氧化物至关重要.
- 这些相位,特别是在形态相位边界,与增强的介电和电机性能有关.
- 这些阶段内的复杂域微观结构尚未得到充分理解.
研究的目的:
- 在铁电矿氧化物中建立统治单临界域微结构的几何原理.
- 编目和描述连接单临床 (MA/MB型) 菌株域的允许域壁.
- 为域壁方向和衍射峰分离提供分析表达式.
主要方法:
- 实施以前的工作[Gorfman等人. (2022) ]用于分析域墙.
- 基于格子不匹配的域墙的分类 ("允许的"域墙 [Fousek & Janovec (1969) ]).
- 使用单临床扭曲参数来导出域壁定向的分析表达式.
主要成果:
- 确定了12个单临床域,形成由84种允许域墙连接的对.
- 它们被分为48个固定指数 (W-墙) 和36个可变指数 (S-墙) 的类别.
- 为域壁方向,转换矩阵和布拉格峰分离提供了表达式.
结论:
- 已制定了单临床域微观结构的几何定律.
- 这项工作为理解和研究复杂的域结构提供了一个框架.
- 促进实验研究,如X射线衍射,在铁电晶体和薄膜.
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