title: Core-level transient absorption spectroscopy as a probe of electron hole relaxation in photoionized H+(H2O)n.
abstract: There is fundamental interest in understanding the coupled nuclear and electronic dynamics associated with charge transfer processes in complex molecules and materials, which are often mediated by electron, electron hole or proton motion. With dramatic improvements in the techniques to generate extreme ultraviolet (XUV) and X-ray femtosecond pulses, it now becomes possible to trigger and probe these kinds of processes in real time. Here we study the dynamics of an electron hole created by photoionization in the valence shell of protonated water clusters H(+)(H(2)O)(n). We demonstrate that the electron hole is strongly correlated with the protons forming the hydrogen bond network. We show that it is possible to probe key aspects of the valence electron hole dynamics and the coupled nuclear motion with femtosecond time resolution by resonantly exciting K-shell 1s electrons to fill the electron hole. This represents an opportunity for X-ray transient absorption spectroscopy.
authors.affiliation: Center for Free-Electron Laser Science, DESY, Notkestraße 85, D-22607 Hamburg, Germany. oriol.vendrell@cfel.de.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Amine Madjet
authors.forename: Oriol
authors.initials: O
authors.lastname: Vendrell
authors.forename: Robin
authors.initials: R
authors.lastname: Santra