原子替代对核心孔放松动态的影响:对Br2和IBr的研究
Nivedita Bhat1, Yeonsig Nam1, Linda Young1,2
1Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, USA.
The Journal of chemical physics
|February 2, 2026
概括
像Br2和IBr这样的重分子中的原子置换会影响X射线诱导的碎片化. 较重的原子减缓解离,影响动能释放 (KER) 并提供对分子动力学的见解.
科学领域:
- 原子和分子物理 原子和分子物理
- 化学物理 化学物理
- 射线科学X射线科学X射线科学
背景情况:
- 内衰变过程对于理解X射线与重分子相互作用至关重要.
- X射线诱导的光动力学和分子碎片化是化学物理学的关键领域.
- 对核心孔放松动态的准确建模对于诸如分子成像等应用至关重要.
研究的目的:
- 为了研究原子替代对核心孔放松和碎片化动态在Br2和IBr在BrK边缘的X射线电离后的原子替代的影响.
- 将实验性X射线/离子巧合数据与电荷分布和动能释放 (KER) 模拟进行比较.
- 阐明分子碎裂中电子和核效应之间的相互作用,特别是在重元素系统中.
主要方法:
- 使用组合实验技术:X射线/离子巧合测量.
- 使用计算方法:蒙特卡洛和分子动力学模拟.
- 对具有2+至8+总电荷的离子分析碎片离子电荷分布和动能释放 (KER).
主要成果:
- 模拟的KER值与Br2和IBr.中的各种碎片化通道的实验数据有很好的一致性.
- 在IBr中用I取代Br的原子,对内电子衰变过程的影响很小.
- 用更重的I原子替换显著影响了核运动,导致分离速度减慢,KER因原子质量增加而接近库伦极限.
结论:
- 原子质量在解离过程中在核运动中起着重要作用,影响X射线电离后释放的动能.
- 该研究强调了电子衰变和重元素分子碎片化中的核动力学之间的复杂相互作用.
- 这些发现为医学疗法,结构生物学和涉及与分子的X射线相互作用的天体物理学提供了有价值的见解.
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