在LaNiO型化物LnReN (Ln = Pr,Nd) 中通过Re2的Dimers形成可能发生Peierls扭曲
Dominik Werhahn1, Amalina T Buda1, Simon Steinberg2
1Department Chemistry, LMU Munich, Butenandtstr. 5-13, 81377, Munich, Germany.
Angewandte Chemie (International ed. in English)
|December 31, 2025
概括
研究人员在高压下合成了新的LnReN2化物矿. 这些材料表现出独特的结构扭曲和磁性排序,扩大了已知的稀土化物景观.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 化 Perowskites 是一种正在发展中的材料类,已知稳定的化合物有限.
- 与超导氧化物相似的阳离子空隙排序的化物特别罕见.
- 由于潜在的新特性,LaNiO2类型的结构是值得关注的.
研究的目的:
- 合成和描述具有扭曲的LaNiO2型结构的新LnReN2材料.
- 研究这些新型化物的结构,电子和磁性特性.
- 探索这些化合物的稳定性和潜在应用.
主要方法:
- 高压,高温合成使用大容量压力机.
- 粉末X射线和中子衍射用于结构分析.
- 电子结构计算 (DFT) 以了解结合和扭曲.
- 磁化测量和磁性中子散射用于磁性表征.
- 温度依赖的粉末X射线衍射用于稳定性研究.
主要成果:
- 在极端条件下成功合成了两种LnReN2 (Ln = Pr, Nd) 材料.
- 观察到一个因Re二分化和ReN4/2层曲而导致的正角扭曲 (o-LnReN2).
- 电子结构分析揭示了化金属酸盐离子和阴离子金属间框架,皮尔尔斯型扭曲可能是二元化的原因.
- 在15.5K的NdReN2中发现了Nd3+时刻的远程反铁磁顺序.
- 确定NdReN2的分解温度大约为750°C.
结论:
- 合成的o-LnReN2材料代表了一种新的化物类别,可以跨越经典的化物,金属间化合物和低维化学物质.
- 观察到的结构和磁性特性突出显示了稀土化物中调性能的潜力.
- 这些发现为在高压合成条件下探索复杂的化物材料开辟了新的途径.
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