了解多铁体BiMn7O12中不同不稳定性的复杂相互作用,使用57Fe探头Mössbauer光谱学
Iana S Soboleva1, Vladimir I Nitsenko1, Alexey V Sobolev1,2
1Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia.
International journal of molecular sciences
|February 10, 2024
概括
本研究使用Mössbauer光谱学研究了铁 bismuth manganite (BiMn7O12) 中的超细相互作用. 它揭示了复杂的结构和磁性过渡,将它们与动态的Jahn-Teller效应联系起来,并提出了自发极化模型.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 四重矿表现出复杂的相变,对于它们的功能性质至关重要.
- 了解超细相互作用是阐明这些材料中磁性和电性的关键.
- 木矿 (BiMn7O12) 是一种有前途的材料,在多铁体中具有潜在的应用.
研究的目的:
- 为了研究Fe-doped BiMn7O12中的超细电磁相互作用.
- 为了将结构和磁性相位过渡与观察到的超精细参数相关联.
- 根据实验数据,开发一种自发偏振模型.
主要方法:
- 采用Mössbauer光谱法,在一个广泛的温度范围 (10K到670K) 上研究了BiMn7O12中的57Fe探头.
- 分析电场梯度 (EFG) 参数和超细相互作用参数.
- 波恩有效电荷模型和有效场方法用于极化分析的应用.
主要成果:
- 在BiMn6.9657Fe0.04O12中观察到一连串的结构和磁相过渡.
- 证实了Bi3+离子的局部二极极时刻,在电相中具有随机定向.
- 动态的Jahn-Teller效应被确定为结构转换之间异常高精度行为的原因.
- 提出了一个模型来描述自发偏振对温度的依赖,并通过实验数据验证.
- 在磁性有序状态中观察到复杂的放松行为.
结论:
- 这项研究提供了关于BiMn7O12结构性,磁性和电性的相互作用的详细见解.
- 动态的Jahn-Teller效应显著影响了材料在相位过渡附近的行为.
- 拟议的模型为理解类似矿结构中的自发偏振提供了一个框架.
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