结合实验和机弹性建模研究,研究3D酸盐基协调材料的低旋转稳定混合晶体
Mousumi Dutta1, Shubham Bisht2, Prabir Ghosh3
1Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
Inorganic chemistry
|September 7, 2023
概括
这项研究探讨了和的混合如何影响协调网络的磁性. 增加含量逐渐抑制这些材料的旋转交叉行为.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学 有机化学
- 磁电化学 磁电化学 磁电化学
背景情况:
- 具有[NiCo1-(bpy) 3][LiCr(ox) 3]系列的协调网络呈现出高度对称的立方3D结构.
- 这些材料具有氧酸盐桥梁Cr3+和Li+离子的阳离子框架,其中有空腔体[NiCo1-(bpy) 32+.
研究的目的:
- 研究[NiCo1-(bpy) 3]系列 (0 ≤ x ≤ 1) 中脱水协调网络的结构和磁性特性.
- 了解Ni (II) 稀释对这些框架内的Co (II) 离子自旋交叉行为的影响.
主要方法:
- 用单晶和粉末X射线衍射分析来研究结构特征.
- 进行了磁感应度测量,以探测旋转交叉现象.
- 机械弹性模型被用来解释观察到的磁性行为.
主要成果:
- 所有混合样本都保持了相纯度和高对称的立方体结构,格子参数随着Ni (II) 度的增加而下降.
- 纯的[Co(bpy) 3[LiCr(ox) 3]由于框架的化学压力,显示了渐进的,不完整的热旋转交叉.
- 增加Ni(II) 含量进一步扩大和减少了旋转交叉,纯的[Ni(bpy) 3[LiCr(ox) 3]没有显示任何旋转交叉;随着Ni(II) 含量增加,旋转交叉的平均温度增加了.
结论:
- 二氧化稀释显著影响磁性行为,通过增加化学压力来抑制旋转交叉.
- 机械弹性模型成功解释了不完整的旋转过渡,并提供了关于不同旋转状态中的Co原子分布的见解.
- 杂质 (Ni原子) 的存在阻碍了Co原子的合作性旋转状态过渡.
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