Ab initio molecular dynamics simulations. Electronic spectra in condensed phase and excited state dynamics.


Project leader


Funding source

Swedish Research Council - Vetenskapsrådet (VR)


Project Details

Start date: 01/01/2007
End date: 31/12/2009
Funding: 2100000 SEK


Description

We have shown in close collaboration with experimental groups that the x-ray absorption and emission spectra (XAS & XES) contain novel information on the structure of water and on excited-state dynamics. The results for the structure of water are controversial and questions all presently available molecular models for water. The XAS of liquid water implies a local structure around the water molecules which is not in agreement with previous models from diffraction experiments and molecular dynamics (MD) simulations. We also showed that the XES in hydrogen bonded systems contains electronic information on excited state dynamics on the time-scale of bond-breaking. Our work on ultra-fast dynamics after core-excitations in H-bonded systems has received considerable attention among time-resolved x-ray spectroscopists. Soft x-ray free electron lasers (FEL) are currently being constructed worldwide to monitor chemical reactions on a femto-second time-scale through optical/x-ray pump-probe experiments. A combination of excited state MD simulations and spectrum calculations will be an essential and remarkably cheap complement for an efficient use of these facilities. Many fundamental catalytic and photo-chemical reactions can be probed with x-ray spectroscopy. I will work on liquid-solid interfaces and the photo-catalytic processes on surfaces and in solution, relevant for energy-related applications, such as solar cells, fuel cells and long-term storage of radio-active waste.

Last updated on 2017-31-03 at 12:58