title: Power-law solvation dynamics in DNA over six decades in time.
abstract: 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.
authors.affiliation: Department of Chemistry and Biochemistry, University of South Carolina, Columbia, 29208, USA.
authors.forename: Daniele
authors.initials: D
authors.lastname: Andreatta
authors.forename: J Louis
authors.initials: JL
authors.lastname: Pérez Lustres
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Kovalenko
authors.forename: Nikolaus P
authors.initials: NP
authors.lastname: Ernsting
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Murphy
authors.forename: Robert S
authors.initials: RS
authors.lastname: Coleman
authors.forename: Mark A
authors.initials: MA
authors.lastname: Berg
mesh_terms: D003374:Coumarins / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D007700:Kinetics; D012995:Solubility; D013050:Spectrometry, Fluorescence
chemical_list: D003374:Coumarins; D004247:DNA; C030123:coumarin