Excited-state dynamics

Time-resolved photo electron spectroscopy (PES) has the potential of monitoring changes in the electronic structure in photo-induced chemical reactions on femto-second time-scale and assisted by theoretical simulations these changes can be ascribed dirctly to the changes in bonding on the time-scale of the bond breaking.

The x-ray emission and photo-electron spectra for liquid water are sampled over instantaneous configuration with different intermolecular interaction and consequent splittings, in particular of the 3a1 state.

In x-ray emission spectroscopy, the electronic structure os complex condensed systems can be probed, but due to the finite life-time of the core-hole also information on ultra-fast dynamics is probed for hydrogen-bonded systems.

Photo-induced dissociation of water molecules occurs of the time-scale of 10 femto-seconds. As a consequence the x-ray emission spectrum contains contributions from the transient O or OH species.