Ultrafast Photoisomerization of Ethylene Studied Using Time-Resolved Extreme Ultraviolet Photoelectron Spectroscopy
Ultrafast Photoisomerization of Ethylene Studied Using Time-Resolved Extreme Ultraviolet Photoelectron Spectroscopy
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使用时间分辨极紫外光电子能谱研究乙烯的超快光异构化
DOI：
10.1021/acs.jpca.2c02468
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Suzuki Toshinori
中科院分区：
文献类型：
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作者：
Karashima Shutaro;Humeniuk Alexander;Glover William J.;Suzuki Toshinori
利用时间分辨光电子能谱技术，在极紫外（EUV，21.7 eV）探测脉冲下，对乙烯从1 ππ* 态的Franck-Condon区到基态产物的光异构化过程进行了真实的实时观测.采用双折射四波混频和高次谐波产生相结合的方法，获得了31 ± 2fs的时间分辨率。160 nm泵浦脉冲产生的原子核波包在10 fs内进入C → C扭曲几何，在接下来的20-30 fs内发生从激发态到基态的布居转移。在小于45 fs的时间内观察到振动高度激发的基态分子的形成，并且它们以0.87和>5 ps的两个时间常数衰减。的光电子能谱的解释支持的垂直电离能计算使用XMS-CASPT 2沿着测地插值的反应路径从弗兰克-康登区域的产品。
The photoisomerization of isolated ethylene (ethene) was observed in real time from the Franck–Condon region in the1ππ* state to ground-state products using time-resolved photoelectron spectroscopy with extreme ultraviolet (EUV, 21.7 eV) probe pulses. A combination of filamentation four-wave mixing and high-order harmonic generation was employed to obtain a temporal resolution of 31 ± 2 fs. The nuclear wave packet created by a 160 nm pump pulse accesses C═C twisted geometries within 10 fs, and the population transfer from the excited to the ground state occurs within the next 20–30 fs. Formation of vibrationally highly excited ground-state molecules was observed in less than 45 fs, and they decayed with two time constants of 0.87 and >5 ps. The interpretation of the photoelectron spectra is supported by vertical ionization energies calculated using XMS-CASPT2 along geodesically interpolated reaction paths from the Franck–Condon region to the products.