Power-Law Solvation Dynamics in DNA over Six Decades in Time
journal contributionposted on 25.05.2005, 00:00 by Daniele Andreatta, J. Louis Pérez Lustres, Sergey A. Kovalenko, Nikolaus P. Ernsting, Catherine J. Murphy, Robert S. Coleman, Mark A. Berg
Time-resolved Stokes shifts in a dye-containing oligonucleotide have been observed over the entire time range from 40 fs to 40 ns. The dynamics fit to a power law with a small exponent of 0.15. Similar relaxation has been seen in proteins but has not been anticipated in DNA. Distinct relaxation components due to specific subcomponents of the system, bulk water, bound water, counterions, backbone, bases, and so on, are not found. The various subcomponents may be so strongly coupled that their motions cannot be treated separately.