• Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/jcsc/104/02/0133-0142

    • Keywords

       

      Electron transfer; fluorescence kinetics; global analysis; rhodamine B

    • Abstract

       

      Dual fluorescence of the lactone form of rhodamine B (LRB) in polar aprotic solvents has been ascribed to two forms of the dye: lactone and zwitterion, which is built up after the dissociation of the lactonic bond in the excited state. We have studied the kinetics of fluorescence in both bands in several aprotic solvents as a function of temperature by the SPC technique using global analysis of the decay curves. It has been found that under certain conditions (solvent, temperature) the decay kinetics of the zwitterion fluorescence cannot be described by monoexponential function. The two-exponential fits of zwitterionic fluorescence decays are discussed in terms of a quenching effect of the surroundings on the excited molecule. The possibility of diabatic (back-) closure of the lactone ring as a deactivation channel is also considered.

    • Author Affiliations

       

      Jerzy Karpiuk1 Zbigniew R Grabowski1 Frans C De Schryver2

      1. Polish Academy of Sciences, Institute of Physical Chemistry, Kasprzaka 44/52, Warsaw - Pl-01224, Poland
      2. Chemistry Department, Catholic University of Heverlee, Celestijnenlaan 200F, Leuven - B-3001, Belgium
    • Dates

       
  • Journal of Chemical Sciences | News

© 2021-2022 Indian Academy of Sciences, Bengaluru.