相关实验视频
Updated: Jun 21, 2025
08:43
Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
18.0K
氧化物和氧盐,化物,化物和化物的新离子半径
Frank C Hawthorne1, Olivier C Gagné1
1Earth Sciences, University of Manitoba, 125 Dysart Road, Winnipeg, Manitoba R3T 2N2, Canada.
概括
这项研究从水晶结构中广泛的键长数据中推导出离子半径. 类型 (2) 方法,比较类似的离子,准确预测属性,不像类型 (1) 方法. 离子半径作为键长度的代理.
科学领域:
- 晶体学和材料科学 材料科学
- 无机化学 无机化学 有机化学
- 固态物理 固态物理
背景情况:
- 离子半径对于预测原子排列和材料特性至关重要.
- 使用离子半径的现有方法面临挑战,因为在离子-离子尺寸比较中存在不确定性.
- 量子力学计算表明离子半径是可变的,与传统用途相冲突.
研究的目的:
- 在晶体结构中从实验确定的键长度得出可靠的离子半径.
- 评估利用离子半径来预测晶体性质的不同方法的有效性.
- 为了使实验性离子半径与量子力学发现相协调.
主要方法:
- 从与氧和结合的离子的大平均键长度得出离子半径.
- 在9,210个晶体结构中分析了来自30,805个协调多面体的177,143个键长 (对于氧).
- 在434个晶体结构 (对于) 中分析了875个协调多面体中的4048个键长.
主要成果:
- 对于与氧的 135 个离子和与的 76 个离子,已确定的特征键长.
- 证明了比较类似离子 (类型2) 的方法可以准确预测地点占用率和属性.
- 展示了依赖于阴离子-离子大小比率的1型方法,由于大小的不确定性,往往会失败.
结论:
- 从特征性键长度得出的离子半径是有效的,特别是在类型 (2) 的比较方法中.
- 离子半径在预测相关性中作为特征键长度的有价值的代理变量.
- 离子半径与局部排列的可变性通过将它们视为键长度的代理来协调.
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