层叠矿氧化的排序和新多态:Sr2VO4-x) H-x)
Joonho Bang1, Satoru Matsuishi, Haruhiro Hiraka
1Materials and Structures Laboratory, ‡Materials Research Center for Element Strategy, and ∥Frontier Research Center, Tokyo Institute of Technology , Yokohama 226-8503, Japan.
Journal of the American Chemical Society
|May 8, 2014
概括
合成了可调节的氧化Sr2VO(4-x) H(x),显示在晶体结构中取代氧气. 这种替代导致了新的有序相,影响了-联体结合相互作用.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 无机化学 无机化学 有机化学
背景情况:
- 氧化是一种具有可调节电子和磁性质的材料.
- 控制阳离子的组成和排序对于理解和优化它们的性能至关重要.
- 以前的合成方法经常导致显著的离子空缺,使属性分析复杂化.
研究的目的:
- 为了合成可调节组合的氧化Sr2VO(4-x) H(x) 与最小的离子空缺.
- 为了研究这些材料中的结构演变和离子排序,作为含量的函数.
- 阐明离子排序和电子结构之间的关系,特别是-联结.
主要方法:
- 合成的高压固态反应.
- 粉末中子衍射和同步子X射线衍射用于晶体结构的确定.
- 用于组合分析的热溶解光谱学.
- 第一原则密度函数理论 (DFT) 计算用于电子结构和结合分析.
主要成果:
- 成功合成了Sr2VO ((4-x) H ((x) (0 ≤ x ≤ 1.01)) 在受控的合和最小的氧空缺的情况下.
- 在VO6层中,选择性取代赤道氧的离子的观测,特别是在低含量 (x < 0.2) 的情况下.
- 从初始四角形 (K2NiF4型) 阶段过渡的高含量 (x > 0.7) 的有序离子形成一个新的正方形 (Immm) 阶段.
- DFT计算显示,氧/离子排序的程度与-联体结合相互作用之间存在强烈的相关性.
结论:
- 可组合调节的氧化可以通过高压方法合成,从而可以精确控制含量.
- 的结合导致了独特的结构相位过渡和离子排序现象.
- 观察到的离子排序显著影响电子性质,突出了在设计功能性材料时结构控制的重要性.
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