在Nd2-xSrxNiO4+δ中,依赖于兴奋剂的结构阶段过渡,磁性顺序和过量的氧气行为
Sumit Ranjan Maity1,2,3, Monica Ceretti4, Lukas Keller2
1Japan Synchrotron Radiation Research Institute (JASRI), SPring-8, Hyogo 679-5198, Japan.
Inorganic chemistry
|December 16, 2025
概括
在多层尼基酸盐中施加的兴奋剂影响了它们的晶体结构和磁性. 这项研究揭示了化学兴奋剂和氧气排序如何影响这些过渡金属氧化物的磁性.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 固态化学 固态化学
背景情况:
- 过渡金属氧化物由于格子,电荷和旋转的相互作用而表现出复杂的行为.
- 层状尼基酸盐,如Nd2-xSrxNiO4+δ,提供了一个平台,通过化学兴奋剂和氧气固体测量来研究这些相互作用.
研究的目的:
- 为了研究Nd2-xSrxNiO4+δ的结构和磁性演变,具有不同的 (Sr) 含量 (x) 和氧非静态度 (δ).
- 了解化学兴奋剂,晶体结构,氧气排序和磁性之间的合在这个系统中.
主要方法:
- 使用高分辨率的同步X射线和中子衍射来分析结构和磁性特性.
- 宏观测量是在广泛的温度范围内进行的.
- 在空气中使用高温固态合成来控制氧气合并.
主要成果:
- 在Nd2NiO4.23 (x=0) 中,氧的结合 (δ > 0) 导致了有序的过剩氧,导致了高达800K的结构调制和过渡.
- 替代抑制了氧气吸收和NiO6八面体倾斜,破坏了氧气的排序.
- 带状旋转顺序与Sr合物出现,x=0.5样本显示磁性不相称性低于95K,表明电荷不相称性.
- 经过Sr-doped的样本表现出准二维磁性,与氧气合相不同.
结论:
- 用Sr进行化学剂显著改变了Nd2-xSrxNiO4+δ的结构和磁场.
- 这项研究强调了化学兴奋剂,晶体结构,氧气排序和层叠的尼基酸盐中出现的磁现象之间的强烈联系.
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