在A2BO4旋氧化物中排序的电离子的通用静电起源
Vladan Stevanović1, Mayeul d'Avezac, Alex Zunger
1National Renewable Energy Laboratory, Golden, Colorado 80401, USA. vladan.stevanovic@nrel.gov
Journal of the American Chemical Society
|June 28, 2011
概括
一个简单的静电模型解释了A(2) BO(4) 旋氧化物中的阴离子排序. 该模型预测了顺序-混乱过渡的特征温度,与阴离子电荷相关,并解释了在3-2和2-4旋转中观察到的混乱水平.
科学领域:
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- A(2) BO(4) 螺旋氧化物表现出基于阴离子分布的正常或逆晶体结构.
- 这些结构经历了取决于温度的秩序和混乱现象.
研究的目的:
- 为了证明一个简单的点离子静电 (PIE) 模型可以自然地解释A(2)BO(4) 旋中的普遍结构变化.
- 使用PIE模型量化预测秩序-混乱过渡温度.
- 为了将离子电荷与这些过渡温度的大小相关联.
主要方法:
- 一个点离子静电 (PIE) 模型的开发和应用.
- 使用PIE哈密尔顿人的蒙特卡洛模拟.
- 分析阴离子分布和秩序障碍现象作为温度的函数.
主要成果:
- 使用单个参数的PIE模型成功地复制了A(2) BO(4) 旋转的特征结构变化.
- 蒙特卡洛模拟提供了定量秩序-混乱特征温度.
- 在阴离子电荷和过渡温度之间建立了直接的相关性,解释了3-2和2-4旋类之间的差异.
结论:
- PIE模型提供了一个基本的框架,用于理解旋转网中的定数排序.
- 基于原子电荷,特征性的秩序-混乱温度是可以预测的.
- 该模型解释了与2-3个旋转相比,在3-2个旋转中观察到的更高程度的障碍,而不是在2-4个旋转中观察到的.
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