1. Division of Chemistry Department of Physics, Chemistry and Biology; Linköping University; 581 83 Linköping Sweden
2. Division of Theoretical Chemistry Department of Physics, Chemistry and Biology; Linköping University; 581 83 Linköping Sweden
3. Sanders-Brown Center on Aging; University of Kentucky; KY 40536-0230 Lexington USA
4. Department of Physics; Norwegian University of Science and Technology; 7491 Trondheim Norway