Institut Lumière Matière, Université Lyon 1, CNRS, UMR 5306, 10 rue Ada Byron, 69622, Villeurbanne Cedex, France.
Theoretische Chemie, PCI, Universität Heidelberg, Im Neuenheimer Feld 229, 69120, Heidelberg, Germany.
Nat Commun. 2019 Jan 18;10(1):337. doi: 10.1038/s41467-018-08131-8.
The many-body quantum nature of molecules determines their static and dynamic properties, but remains the main obstacle in their accurate description. Ultrashort extreme ultraviolet pulses offer a means to reveal molecular dynamics at ultrashort timescales. Here, we report the use of time-resolved electron-momentum imaging combined with extreme ultraviolet attosecond pulses to study highly excited organic molecules. We measure relaxation timescales that increase with the state energy. High-level quantum calculations show these dynamics are intrinsic to the time-dependent many-body molecular wavefunction, in which multi-electronic and non-Born-Oppenheimer effects are fully entangled. Hints of coherent vibronic dynamics, which persist despite the molecular complexity and high-energy excitation, are also observed. These results offer opportunities to understand the molecular dynamics of highly excited species involved in radiation damage and astrochemistry, and the role of quantum mechanical effects in these contexts.
分子的多体量子性质决定了它们的静态和动态特性，但仍是准确描述它们的主要障碍。超短极紫外脉冲为揭示超快时间尺度下的分子动力学提供了一种手段。在这里，我们报告了使用时间分辨电子动量成像与极紫外阿秒脉冲结合来研究高激发有机分子。我们测量了随态能量增加的弛豫时间尺度。高精度量子计算表明，这些动力学是与时间相关的多体分子波函数内在相关的，其中多电子和非玻恩-奥本海默效应完全纠缠在一起。尽管分子复杂性和高能激发存在，我们也观察到了相干的振子动力学的迹象。这些结果为理解涉及辐射损伤和天体化学的高激发物种的分子动力学以及这些情况下量子力学效应的作用提供了机会。
