在BaIrO的高压序列中出现了一种新的矿聚类型 ((3))
Jin-Guang Cheng1, José Antonio Alonso, Emmanuelle Suard
1Texas Materials Institute, ETC 9.102, The University of Texas at Austin, Austin, Texas 78712, USA.
Journal of the American Chemical Society
|May 28, 2009
概括
iridate (BaIrO3) 呈现出独特的高压序列的矿多类型,包括一个新的5H结构. 这种行为不同于典型的过渡金属氧化物,原因是强烈的-键和排斥.
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:
- iridate (BaIrO3) 是一种复杂的氧化物,具有各种矿多种类型.
- 了解BaIrO3在压力下的结构转变对于材料科学至关重要.
研究的目的:
- 为了研究BaIrO3高达10 GPa的矿聚类型的高压序列.
- 使用衍射技术来描述这些多型的晶体结构.
主要方法:
- 固态反应和缓慢冷却用于环境压力合成.
- 用X射线衍射 (XRD) 和中子粉衍射 (NPD) 来精制晶体结构.
- 对于结构解决方案的初始计算.
主要成果:
- 9R多型 (hhchhc堆叠) 稳定性高达3 GPa.
- 一种新的5H多型 (hchcc堆叠) 稳定在4到5GPa之间.
- 6H多型 (hcchcc堆叠) 稳定在5GPa到10GPa之间,在10GPa出现一个小的3C矿阶段.
结论:
- BaIrO3具有独特的压力诱导多型序列 (9R-5H-6H-3C),与其他过渡金属氧化物不同.
- 9R相的稳定性和Ir-Ir相互作用影响了这种新奇的序列,特别是5H多型的稳定性.
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