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Ultrafast Structural Dynamics of Photo-Reactions Revealed by Model-Independent X-ray Cross-Correlation Analysis

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 نشر من قبل Ivan Vartanyants
 تاريخ النشر 2018
  مجال البحث فيزياء
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We applied angular X-ray Cross-Correlation analysis (XCCA) to scattering images from a femtosecond resolution LCLS X-ray free-electron laser (XFEL) pump-probe experiment with solvated PtPOP ([Pt$_2$(P$_2$O$_5$H$_2$)$_4$]$^{4-}$) metal complex molecules. The molecules were pumped with linear polarized laser pulses creating an excited state population with a preferred orientational (alignment) direction. Two time scales of $1.9pm1.5$ ps and $46pm10$ ps were revealed by model-independent XCCA, associated with an internal structural changes and rotational dephasing, respectively. Our studies illustrate the potential of XCCA to reveal hidden structural information in a model independent analysis of time evolution of solvated metal complex molecules.



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