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Synthesis of In37P20(O2CR)51 Clusters and Their Conversion to InP Quantum Dots
Published on: May 7, 2019
Telluride (II'): 转化过程中的过渡性中间阶段,从InTe (II) 转变为InTe (I)
概括
化 (InTe) 经历相变. 在高压下,InTe(II) 转化为暂时的InTe(II') 多态,然后在环境压下转化为稳定的InTe(I).
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 化 (InTe) 在不同压力和温度条件下表现出复杂的相位行为.
- 了解InTe的多态性对于其在电子和热电设备中的潜在应用至关重要.
研究的目的:
- 为了研究 telluride 的高压相变.
- 为了描述新发现的 telluride 的过渡多态体.
- 为了确定 telluride 多态体的转换动力学.
主要方法:
- 高压X射线衍射研究以确定晶体相.
- 不同扫描热量计 (DSC) 监测相位过渡.
- 温度依赖的X射线衍射研究转换速率.
主要成果:
- 高压立方体InTe(II) 在1大气中转化为一个过渡的四边形多态,InTe(II").
- 新的InTe(II") 多态体具有单元细胞尺寸a(0) = 6.06 Å和c(0) = 6.55 Å.
- 转换速率取决于温度:InTe(II) 到InTe(II") 在60°C以上是快速的,而InTe(II") 到InTe(I) 在125°C以上是快速的.
结论:
- 已经确定了 telluride 的一种新型过渡性多态,InTe ((II").
- 从高压InTe (II) 到稳定的InTe (I) 的转换途径涉及一个中间阶段.
- 这些相变的动力学受到温度的显著影响,为材料加工提供了洞察力.
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