在双矿Ba2MnWO6中的磁挫折的化调
Judith Oró-Solé1, Carlos Frontera1, Jhonatan R Guarín1
1Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain.
Chemistry of materials : a publication of the American Chemical Society
|March 24, 2025
概括
在低温下合成了一种新的双矿氧化,Ba2MnWO4.42N1.58,保持了阴离子顺序. 与其氧化物前体相比,这种材料表现出增强的磁自旋挫折.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 磁力学 磁力学 是一种
背景情况:
- 双矿氧化物是具有调节性质的多功能材料.
- 氧化化物类似物为修改电子和磁性行为提供了机会.
- 了解复杂的过渡金属化合物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双矿氧化,Ba2MnWO4.42N1.58.8.
- 为了研究新氧化的结构和磁性特性.
- 为了比较氧化与其氧化物前体中的磁性挫折.
主要方法:
- 在700°C的高化学氨解Ba2MnWO6与高NH3流速.
- 同步射线X射线衍射,电子衍射和中子衍射用于结构分析.
- 测量磁性易感度,以确定磁性排序温度和挫折度.
主要成果:
- Ba2MnWO4.42N1.58 在 Fm3̅m 空间组中结晶,其格子参数为 8.2434(5) Å.
- 在T<0xE2><0x82><0x99> = 3.8K以下观察到的抗铁磁排序,与氧化物 (f ≈ 7.2) 相比,挫折参数 (f ≈ 18) 显著增强.
- 化物替代导致Mn氧化 (Mn2+到Mn3+/4+) 并降低有效磁矩.
结论:
- 低温合成保持了阴离子顺序,产生了一个新的双矿氧化.
- 替代增强了由于改变的Mn-Mn相互作用和增加的共价性而导致的磁旋挫折.
- 这项工作扩大了复杂氧化物的范围,并提供了一条调整矿材料中旋转挫折的途径.
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