在高压下揭示了酸的聚乙烯相
Himal Bhatt1,2, Ashok K Verma1,2, P Modak1,2
1High Pressure & Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India. hbhatt@barc.gov.in.
概括
在高压下,酸 (FA) 转化为以太链聚合物,然后进入循环以太阶段. 红外实验证实了FA的这些新型高压结构.
科学领域:
- 高压物理和化学 高压物理和化学
- 材料科学是一种材料科学.
- 固态化学 固态化学
背景情况:
- 酸 (FA) 是最简单的碳酸.
- 了解分子固体的高压行为对于凝聚物质物理学至关重要.
- 之前关于FA在压力下的研究表明了不同的结构过渡.
研究的目的:
- 为了研究酸的高压结构演变.
- 在极端条件下识别FA的新阶段和过渡.
- 用实验证据验证理论预测.
主要方法:
- 用进化结构搜索来预测FA的潜在高压阶段.
- 理论计算是在高达20GPa和高于60GPa的压力下进行的.
- 进行了红外光谱实验,以探测振动模式并确认预测的结构.
主要成果:
- 在 20 GPa 时,FA 转化为正方体以太链聚合物相,而不是键对称.
- 在60GPa以上,FA的新型冠冕循环-四角相出现.
- 红外实验显示出特有的聚和新的OH拉伸模式,验证了预测的结构.
结论:
- 酸在高压下表现出复杂的结构演变,形成不同的聚合物和循环相.
- 这些发现挑战了以前关于高压下FA中键对称化的假设.
- 这项研究揭示了FA的多方面的进化,其聚合物链结构类似于聚氧甲等宇宙聚合物.
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