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arXiv · 1811.07973

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

Peter Vester·Ivan A. Zaluzhnyy·Ruslan P. Kurta·Klaus B. Moeller·Elisa Biasin·Kristoffer Haldrup·Martin Meedom Nielsen·Ivan A. Vartanyants
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Abstract

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 $1.9\pm1.5$ ps and $46\pm10$ 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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Peter Vester, Ivan A. Zaluzhnyy, Ruslan P. Kurta, Klaus B. Moeller, Elisa Biasin, Kristoffer Haldrup, Martin Meedom Nielsen, Ivan A. Vartanyants. 2018-11-19. Ultrafast Structural Dynamics of Photo-Reactions Revealed by Model-Independent X-ray Cross-Correlation Analysis. https://doi.org/10.1063/1.5086374

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