在液体硫中存在短链的证据
Chris J Benmore1, Ganesh Sivaraman2
1X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA.
The Journal of chemical physics
|October 15, 2024
概括
液体硫是一种液体硫.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- 长期以来,硫的独特相位转换,特别是羊羔转换,一直让科学家们感到好奇.
- 广泛接受的模型建议液体硫仅由S8环组成.
研究的目的:
- 通过兰巴达过渡来研究液体硫的局部原子结构.
- 挑战目前流行的液体硫的组成和结构模型.
主要方法:
- 高能X射线散射的实验. 高能X射线散射的实验.
- 配对分布函数 (PDF) 的分析.
- 进行X射线结构因子 (XSF) 分析.
主要成果:
- 液体硫中的平均第一协调数为1.86 ± 0.04,而不是2.0.
- 在液体硫中存在短链和"间隙原子"的证据.
- 在XSF和PDF中Lambda过渡的偏差表明环开放和聚合.
结论:
- 液体硫含有大量的短链和间隙原子,而不仅仅是S8环.
- 这些结构特征对于启动S8环到链过渡至关重要.
- 这些发现与最近的硫聚合的分子动力学模拟相一致.
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