非常稳定的"ortho"-Nitroaniline离子体的光解离动力学
Hugo A López Peña1, Jacob M Shusterman1, Clayton Dalkiewicz1
1Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States.
The journal of physical chemistry. A
|February 27, 2024
概括
由于高电子激发状态和解离障碍,正-尼林 (ONA) 离子表现出了显著的稳定性. 五秒时分辨率质谱证实了ONA的离子稳定性,需要大量的能量来解离.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 计算化学的计算化学
背景情况:
- 欧托尼氨酸 (ONA) 作为一种模范化合物,用于不敏感的高爆炸物,如TATB.
- ONA在和氨基群之间表现出强大的分子内键.
研究的目的:
- 通过实验和理论方法研究ONA的稳定性.
- 与相关的酸芳香分子相比,阐明了导致ONA的高稳定性的因素.
主要方法:
- 在探头测量中使用了5秒时间分辨率质谱法 (FTRMS).
- 进行了ab initio计算以确定电子激发状态和反应障碍.
主要成果:
- 的最低电子激发状态 (D1) 在基态上方超过2 eV.
- 重组和解离的能量障碍超过了D1能量.
- 在强烈的激光脉冲下,FTRMS证实了最小的碎片化 (<30%),并且需要3.1 eV的光子来解离.
结论:
- 的稳定性归因于它的电子结构和高解离能障碍.
- 实验结果与理论预测一致,验证了稳定性模型.
- 在几何放松之前,由于D0和D4状态之间的合,观察到过渡的碎片增强.
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