INFLUENCE OF NON-DEBYE RELAXATION AND OF MOLECULAR SHAPE ON THE TIME DEPENDENCE OF THE STOW SHIFl- IN POLAR MEDIA

نویسندگان

  • Edward W. CASTNER
  • Graham R. FLEMING
  • Biman BAGCHI
چکیده

We present theoretical analyses of two different aspects ofthe time dependence of the fluorescence Stokes shift in polar liquids. We show that a small deviation from the Debye form for the dielectric relaxation of the solvent can strongly influence the time evolution of the Stokes shift. Using the Davidson-Cole form for dielectric response we find a stretched exponential time dependence as observed in recent experiments. We also show that the shape of the fluorescing molecule can influence the dynamics of solvation.

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تاریخ انتشار 2005