在氧化中探索多离子化学:固态NMR研究和DFT计算
Shrestha Banerjee1, Diana Chaykina2, Rens Stigter3
1Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, NL-6525 AJ Nijmegen, The Netherlands.
稀土氧化化物表现出光色,随着光线的变化而改变颜色. 这项研究使用NMR和DFT揭示了它们的复杂结构和动态,识别了富含化物和缺乏化物的领域以及分子的形成.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 频谱学是一种光谱学.
背景情况:
- 具有FCC格子的稀土氧化 (REOH) 已知具有光色.
- 结构,离子组成和光色效率之间的关系已经确立,但潜在的机制仍然不清楚.
研究的目的:
- 为了阐明稀土氧化的光色化机制.
- 调查局部环境,阴离子氧化状态和氧化 (YOH) 中的离子动态.
主要方法:
- 固态核磁共振 (NMR) 光谱 (1H, 2H, 17O, 89Y).
- 密度函数理论 (DFT) 计算用于模拟YOH结构和属性.
- 2D NMR相关性实验以探测样本异质性.
主要成果:
- DFT模型与有序和无序的YOH子线的实验性NMR数据相对应得很好.
- 核磁共振显示了样本的异质性,其中含有富含化物 (x ≈ 0.25) 和缺乏化物 (x ≈ 1) 的域.
- 氧化物离子 (OH−) 的存在和通过质子化物反应形成分子 (H2),在1H NMR中观察到作为移动元件.
结论:
- 光色化机制涉及异质性和分子的形成.
- 结构和组成细节,包括域形成和H2捕获,对于理解稀土氧化的光色行为至关重要.
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