解析时间分辨的粒子间库仑衰变：从光谱形成到衰变寿命
Unravelling time-resolved Interparticle Coulombic Decay: From spectral formation to decay lifetimes
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中文总结 AI 辅助
研究氖二聚体中粒子间库仑衰变，扩展时间分辨电子衰变光谱解析描述纳入解离核动力学，通过理论与实验结合，揭示核运动对光谱影响，修正ICD寿命，对从时间分辨衰变光谱提取寿命有广泛意义。
中文摘要 AI 辅助
电子衰变过程为超快时间尺度上的相关电子重排提供了一个迷人的窗口。实时追踪这些动力学在实验上越来越可行，但从测量光谱中提取潜在的电子动力学需要理解核运动如何塑造可观测信号。在此，我们扩展了时间分辨电子衰变光谱的解析描述以纳入解离核动力学，并将其应用于氖二聚体中的粒子间库仑衰变（ICD）。所得光谱再现了实验观测到的光谱形状，并揭示了涉及不同振转共振态的路径间干涉出人意料的重要作用。我们进一步在光谱结构的时间积累与衰变电子态中的核波包动力学之间建立了明确联系。最引人注目的是，我们的解析表达式表明，随时间变化的积分ICD信号包含与\(\exp(-t/\tau)\)和\(\exp[-t/(2\tau)]\)成比例的贡献。然而，传统的单指数拟合能很好地描述时间信号，同时给出与实际值有显著差异的衰变寿命。将理论推导的拟合模型应用于氖二聚体的实验数据，得到ICD寿命\(\tau\)为73 fs，而非之前提取的150(50) fs，使实验值处于先前理论预测范围内。由于潜在的时间结构是电子衰变过程共有的，我们的发现对从时间分辨衰变光谱中提取寿命具有广泛意义，远超ICD。
英文摘要
Electronic decay processes provide a fascinating window into correlated electronic rearrangements occurring on ultrafast timescales. Following these dynamics in real time has become increasingly accessible experimentally, but extracting the underlying electronic dynamics from measured spectra requires understanding how nuclear motion shapes the observable signal. Here, we extend an analytical description of time-resolved electronic decay spectra to include dissociative nuclear dynamics and apply it to Interparticle Coulombic Decay (ICD) in the neon dimer. The resulting spectra reproduce the experimentally observed spectral shape and reveal an unexpectedly important role of interference between pathways involving different vibronic resonance states. We further establish a clear connection between the temporal build-up of the spectral structure and the nuclear wavepacket dynamics in the decaying electronic state. Most strikingly, our analytical expressions reveal that the time-dependent integrated ICD signal contains contributions proportional to both $\exp(-t/τ)$ and $\exp[-t/(2τ)]$. Nevertheless, a conventional mono-exponential fit can describe the temporal signal remarkably well while yielding a decay lifetime that differs substantially from the underlying value. Applying the theoretically derived fitting model to experimental data for the neon dimer yields an ICD lifetime $τ$ of 73 fs, rather than the previously extracted 150(50) fs, placing the experimental value within the range of previous theoretical predictions. Since the underlying temporal structure is common to electronic decay processes, our findings have implications for extracting lifetimes from time-resolved decay spectra well beyond ICD.
