1. Bayer Technology Services GmbH, Competence Center Biophysics, D-51368 Leverkusen, Germany (E.D., S. W., P.K.); and Institute of Spectrochemistry and Applied Spectroscopy (ISAS) at the University of Dortmund, Bunsen-Kirchhoff-Str. 11, D-44139 Dortmund, Germany (R.K., U.D., H.M.H.)