富含的金属间相ARh2Cd20 - 结构,磁性行为,151Eu Mössbauer和113Cd固态NMR光谱学
Lars Schumacher1, Florian Schreiner2, Aylin Koldemir1
1Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, 48149 Münster, Germany. pottgen@uni-muenster.de.
Dalton transactions (Cambridge, England : 2003)
|January 28, 2025
概括
新的富含的金属间化合物A-Rh2Cd20被合成和特征. 磁性和NMR研究揭示了各种磁性行为,包括铁磁性和反铁磁性,Eu和Yb的稳定双价态.
科学领域:
- 固态化学和物理. 固态化学和物理.
- 金属间化合物的材料科学.
- 在稀土和过渡金属化合物中的磁性和磁性排序.
背景情况:
- A-Rh2Cd20 (A = Ca, Sr, Y, La-Nd, Sm-Lu) 系列代表富含的金属间化合物.
- 了解这些化合物的结构性,磁性和电子性质对于探索新材料至关重要.
- 之前对类似金属间化合物的研究为研究新阶段提供了基础.
研究的目的:
- 为了合成和表征A-Rh2Cd20石化学的新丰富的金属间化合物.
- 为了研究这些合成化合物的晶体结构,磁性和电子状态.
- 探索磁性排序现象,包括铁磁性,反铁磁性和超磁性过渡.
主要方法:
- 在密封的管中从元素前体合成A-Rh2Cd20化合物,随后进行感应炉反应和后.
- 使用X射线粉碎衍射和X射线单晶衍射计进行晶体学表征,以精制结构.
- 在温度范围内的磁感应度测量,151Eu Mössbauer光谱和固态NMR光谱 (113Cd,103Rh,139La,89Y,171Yb).
主要成果:
- A-Rh2Cd20 阶段结晶成立方 CeCr2Al20 型结构 (空间组 Fd-3m).
- 磁性易感性揭示了几个化合物的二磁性 (例如,CaRh2Cd20,YbRh2Cd20),表明稳定的双价Yb.
- 在EuRh2Cd20 (Tc = 13.8 K) 中观察到铁磁排序,在SmRh2Cd20,GdRh2Cd20,TbRh2Cd20 和 DyRh2Cd20 中观察到反铁磁排序.
- 在TbRh2Cd20和DyRh2Cd20中检测到元磁转换.
- NMR和Mössbauer光谱证实了Eu和Yb的稳定双价态,并提供了对本地电子环境和相互作用的见解.
结论:
- A-Rh2Cd20化合物表现出由特定的稀土元素驱动的各种磁性行为.
- 通过多种实验技术,在特定阶段确认了稳定的双价值Eu和Yb离子的存在.
- 该研究提供了对这种类型的富含的金属间材料的结构和磁性特性的全面了解.
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