MnCaTa2O7-一个通过阴子交换制备的磁性排序的极相
Subhadip Mallick1, Fabio Orlandi2, Pascal Manuel2
1Department of Chemistry, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, UK.
Chemistry of materials : a publication of the American Chemical Society
|October 2, 2023
概括
合成的MnCaTa2O7揭示了一个极性反铁磁阶段与格子异常. 与相关材料不同,它缺乏弱铁磁性,突出显示了阴离子顺序对铁电性质的影响.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 伪Ruddlesden-Popper阶段是复杂的氧化物材料的前体.
- 具有极性扭曲模式的分层矿对铁电应用具有兴趣.
- 了解过渡金属酸中的结构性质关系至关重要.
研究的目的:
- 为了合成和表征一种新的含Mn的分层矿,MnCaTa2O7.
- 研究其磁性和结构性质,特别是其极性和磁性排序.
- 将其行为与相关的MnATa2O7相进行比较,以了解结构属性相关性.
主要方法:
- 固态反应合成.
- 测量磁感应度的测量.
- 中子衍射分析. 中子衍射分析.
- 对格子参数和极性扭曲模式的分析.
主要成果:
- 合成的MnCaTa2O7是一种极相 (P21nm),具有扭曲的层叠矿结构.
- 在TN=56K以下观察到抗铁磁排序,在TA=50K时有显著的晶格异常和极态增强.
- 与MnSrTa2O7不同,MnCaTa2O7没有表现出弱铁磁性或磁电合.
结论:
- 观察到的MnCaTa2O7的物理性质受到Mn离子顺序和TaO6倾斜模式的强烈影响.
- 混合不当铁电器中的微妙结构变化可以导致扭曲模式合和新兴现象的显著差异.
- 在MnCaTa2O7中没有磁电合,与相关相相对比,强调了这些材料对结构细节的敏感性.
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