Departamento de Química, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
Dipartimento di Scienze Chimiche e Farmaceutiche, Universitá di Trieste, 34127, Trieste, Italy.
Chemistry. 2018 Aug 14;24(46):12061-12070. doi: 10.1002/chem.201802788. Epub 2018 Jul 27.
A pump-probe experiment in the tetrafluoro-methane (CF ) molecule has been theoretically simulated, allowing one to access electron dynamics in its natural time scale: the attosecond. The chosen pump and probe pulses can be currently produced in most attosecond laboratories. In this scheme, CF is first ionized by an extreme UV (XUV) attosecond pulse and the charge dynamics induced in the corresponding cation is probed with a few-femtosecond visible light (VIS) pulse. We demonstrate that modulations in the calculated photoelectron spectra with the pump-probe delay reflect the dynamics of the XUV-induced electronic wave packet. In particular, from the analysis of these modulations in the interval of time delays where the pump and probe pulses do not overlap any more, one has access to the amplitudes and phases of the different components of the electronic wave packet generated by the attosecond pulse. These reflect a complex dynamics that basically consists of very fast charge fluctuations occurring all over the molecule without any preference for a particular molecular site.
已经对四氟甲烷（CF ）分子中的泵浦-探测实验进行了理论模拟，使人们能够在其自然时间尺度（阿秒）内获取电子动力学信息。所选的泵浦和探测脉冲目前可以在大多数阿秒实验室中产生。在该方案中，首先用极紫外（XUV）阿秒脉冲将 CF 离子化，并用几飞秒可见光（VIS）脉冲探测相应阳离子中诱导的电荷动力学。我们证明，计算出的光电子能谱与泵浦-探测延迟之间的调制反映了 XUV 诱导的电子波包的动力学。特别是，通过分析在泵浦和探测脉冲不再重叠的时间延迟间隔内的这些调制，可以获得由阿秒脉冲产生的电子波包的不同分量的振幅和相位。这些反映了一种复杂的动力学，基本上由整个分子中没有任何特定分子位置偏好的非常快速的电荷波动组成。
