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在压缩到35 GPa时,在钻石天细胞中,二烯的多态性

Wenju Zhou¹, Yuqing Yin², Dominique Laniel³

¹Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, Bayreuth, Germany. Wenju.Zhou@uni-bayreuth.de.

Communications chemistry

|September 16, 2024

概括

高压研究揭示了二烯的新相,包括二烯-IV和二烯-V,高达35 GPa. 压缩导致分子曲率,在大型有机分子中表现出意想不到的灵活性.

科学领域:

材料科学材料科学材料科学
固态化学固态化学
有机化学有机化学

背景情况:

之前的烯结构研究仅限于低于2 GPa的压力.
了解多环芳 (PAHs) 的高压行为对于材料科学至关重要.

研究的目的:

在高压下 (高达~35 GPa) 调查二烯的结构相变.
在极端压力下分析烯的分子包装,结合和构造变化.
将实验结果与理论预测进行比较.

主要方法:

在钻石天细胞中的in-situ单晶同步X射线衍射.
Ab initio计算用于理论分析和相位比较.

主要成果:

确定了从pyrene-I到pyrene-II (0.7 GPa),pyrene-IV (2.7 GPa) 和pyrene-V (7.3 GPa) 的相位过渡.
观察到持续的紧缩导致分子曲率,这是pyrene的一个新奇现象.
证明了二烯的显著构造灵活性,保持二烯-V高达35 GPa.
Ab initio计算表明,与pyrene-III相比,观察到的相在热力学上是不稳定的.

结论:

这项研究扩大了对二烯高压多态性的理解.
这些发现凸显了压缩下大型有机分子的意想不到的结构灵活性.
建议进行进一步的理论研究,以探索PAHs中的结构属性关系.

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