一个异常的高压阶段和解压诱导的模态化在dinitrotoluene
Ashutosh Mohan1, Krishan K Pandey1, Ajay K Mishra1
1High Pressure & Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India and Homi Bhabha National Institute, Mumbai 400094, India.
The Journal of chemical physics
|December 10, 2025
概括
高压将2,4-丁二二烯 (2,4-DNT) 通过相变和改变的键转化. 解压揭示了不同的恢复路径,包括无形化,影响能量分子固体的稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 物理 物理学 物理
背景情况:
- 能量分子固体对于各种应用至关重要.
- 了解它们的高压行为是预测稳定性和性能的关键.
- 2,4-丁二二烯 (2,4-DNT) 是一种有能量材料,其对压力的反应尚未完全理解.
研究的目的:
- 为了研究2,4-丁二烯 (2,4-DNT) 的高压行为.
- 描述相位转换,结构变化和压力下的可压缩性.
- 为了比较2,4-DNT与三二烯 (TNT) 的行为,并了解解压路径.
主要方法:
- 在现场的拉曼光谱学高达~19 GPa.
- 同步射线X射线衍射高达~12.3 GPa.
- 压缩,相位转换和解压缩恢复的分析.
主要成果:
- 拉曼光谱检测到1.5GPa附近的形状变化和4-8GPa之间的相变.
- X射线衍射证实了在4.5GPa的阶段过渡开始,完成了8.4GPa.
- 环境和高压阶段均表现出负线性压缩性;高压阶段显示出1D顺序和新的键.
- 2,4-DNT具有比TNT (~80 cm-1) 更大的声子间隙 (~104 cm-1),这表明冲击灵敏度较低.
- 从≤10 GPa的减压导致歇斯底里束的恢复到环境阶段.
- 由于键网络的变化,减压从≥12.3 GPa诱导的无形化.
结论:
- 高压会导致2,4-DNT的结构和形状发生显著的变化,包括相位过渡和改变的键.
- 压力诱导的变化影响了2,4-DNT的冲击灵敏度和解压行为.
- 功能组相互作用和压力史极大地影响了像2,4-DNT和TNT这样的能量分子晶体中的相位稳定性和无形化.
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