Different timescales during ultrafast stilbene isomerisation in the gas and liquid phases revealed using time-resolved photoelectron spectroscopy
Different timescales during ultrafast stilbene isomerisation in the gas and liquid phases revealed using time-resolved photoelectron spectroscopy
复制标题
使用时间分辨光电子能谱揭示气相和液相超快二苯乙烯异构化过程中的不同时间尺度
作者：
Chuncheng Wang;Max D. J. Waters;Pengju Zhang;Jiří Suchan;Vít Svoboda;T. Luu;C. Perry;Z. Yin;P. Slavíček;H. Wörner
直接对比气相和液体中的超快激发态动力学对于理解复杂环境的影响至关重要。以前的研究通常依赖于不同的光谱观察值，这使得直接比较具有挑战性。在这里，我们将极紫外光时间分辨光电子能谱应用于气态和液态顺式二苯乙烯，揭示了其异构化背后的电子和核耦合动力学。我们的测量跟踪了激发态波包，从激发沿整个反应路径到最终产物。我们在物质的两个相中观察到相干的激发态振动动力学，并持续到最终产物，从而能够表征S1-S0锥形交点的分支空间。我们观察到液体中的弛豫时间有系统地延长，测量到的激发态频率发生红移，这在复杂的反应坐标中最为明显。这些结果详细描述了在完全光化学转化过程中，液体环境对电子动力学和结构动力学的影响。人们对液体环境对分子超快激发态动力学的影响知之甚少。利用时间分辨光电子能谱，二苯乙烯在气相和液体中的光异构化动力学现在已被证明是定性相似的--包括观察到振动相干--但在液体中的时间尺度要长得多。
Directly contrasting ultrafast excited-state dynamics in the gas and liquid phases is crucial to understanding the influence of complex environments. Previous studies have often relied on different spectroscopic observables, rendering direct comparisons challenging. Here, we apply extreme-ultraviolet time-resolved photoelectron spectroscopy to both gaseous and liquid cis-stilbene, revealing the coupled electronic and nuclear dynamics that underlie its isomerization. Our measurements track the excited-state wave packets from excitation along the complete reaction path to the final products. We observe coherent excited-state vibrational dynamics in both phases of matter that persist to the final products, enabling the characterization of the branching space of the S1–S0 conical intersection. We observe a systematic lengthening of the relaxation timescales in the liquid phase and a red shift of the measured excited-state frequencies that is most pronounced for the complex reaction coordinate. These results characterize in detail the influence of the liquid environment on both electronic and structural dynamics during a complete photochemical transformation. The influence that liquid environments have on the ultrafast excited-state dynamics of molecules is poorly understood. Using time-resolved photoelectron spectroscopy, the dynamics of the photoisomerization of stilbene in the gas and liquid phases have now been shown to be qualitatively similar—including the observation of vibrational coherences—but the timescales are significantly longer in the liquid phase.
绘制复杂光化学反应的完整反应路径。
影响因子：
8.6
作者：
Smith AD
通讯作者：
Smith AD
影响因子：
8.6
作者：
S. Thürmer;R. Seidel;M. Faubel;W. Eberhardt;J. Hemminger;S. Bradforth;B. Winter
通讯作者：
S. Thürmer;R. Seidel;M. Faubel;W. Eberhardt;J. Hemminger;S. Bradforth;B. Winter
影响因子：
56.9
作者：
SCHOENLEIN, RW;PETEANU, LA;SHANK, CV
通讯作者：
SHANK, CV