The chemical composition of the interstellar medium and planetary atmospheres is constantly in flux as atoms and molecules collide and interact with high-energy particles such as electrons, protons, and photons. These transformative processes ultimately lead to the coalescence of molecules and eventually the birth of stars. Our understanding of these chemical ecosystems relies on models that synthesize data from gas-phase experiments, providing insights into reaction cross sections. This Review examines efforts to delve into the fundamental bond-forming and bond-breaking dynamics that occur during bimolecular and electron-initiated reactions. These experiments involve clever approaches to establish a time reference and the collision geometry necessary for tracking atomic motion with femtosecond time resolution. Findings from these efforts enhance present models and improve predictions for molecule-molecule and electron-molecule collisions.

中文翻译：

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难以捉摸的气相化学反应的超快研究


当原子和分子与电子、质子和光子等高能粒子碰撞和相互作用时，星际介质和行星大气的化学成分不断变化。这些转变过程最终导致分子的合并，并最终导致恒星的诞生。我们对这些化学生态系统的理解依赖于合成气相实验数据的模型，提供对反应横截面的见解。本综述探讨了深入研究双分子和电子引发反应期间发生的基本成键和断键动力学的努力。这些实验涉及建立时间参考和以飞秒时间分辨率跟踪原子运动所需的碰撞几何结构的巧妙方法。这些努力的结果增强了现有模型并改进了对分子-分子和电子-分子碰撞的预测。