Exciton Splitting Of Fluorescein Disodium In Polyethylene Glycol 600

The absorption and emission spectra of fluorescein disodium at various concentrations and temperatures were studied using polyethylene glycol 600 as solvent. From the results obtained, it can be concluded that the geometry of the aggregate changes with the physical state of the solvent: the geometry at low temperatures (polymer in the glass state) involves two molecules of the dye in a sandwich orientation; the geometry in the liquid state involves a linear configuration of the monomers. The exciton splitting of the energy levels of the aggregate in the sandwich orientation can be obtained from the fluorescence spectra as 1180 cm-1. The dependence of the fluorescence spectra on the temperature enables the changes in the geometry of the aggregates and the relaxation temperatures of the polymer chains to be investigated. © 1991.591123130Birks, (1960) Photophysics of Aromatic Molecules, , Wiley-Interscience, New YorkPant, Pant, (1968) Indian J. Pure Appl. Phys., 6, p. 238Pant, Bhagghandani, Pant, Verna, (1971) Chem. Phys. Lett., 9, p. 546Rohatgi, Mukhopalhyay, (1972) J. Phys. Chem., 76, p. 3970Arbeloa, Flourescence quantum yield evaluation: corrections for re-absorption and re-emission (1980) Journal of Photochemistry, 14, p. 97Arbeloa, Flourescence self-quenching of Halofluorescein dyes (1982) Journal of Photochemistry, 18, p. 161Arbeloa, (1981) J. Chem. Soc., Faraday Trans. 2, 77, p. 1725Arbeloa, (1981) J. Chem. Soc., Faraday Trans. 2, 77, p. 1735Pant, Bhagghandani, Pant, Verna, (1971) Indian J. Pure Appl. Phys., 9, p. 824Rohatgi, (1968) J. Mol. Spectrosc., 27, p. 545Kasha, Rawls, El-Bayoumi, The exciton model in molecular spectroscopy (1965) Pure and Applied Chemistry, 11, p. 371Lang, Noel, Legrand, (1977) J. Polym. Sci., 15, p. 1319. , Polym. Phys. EdLang, Noel, Legrand, (1977) J. Polym. Sci., 15, p. 1329. , Polym. Phys. EdSabadini, Atvars, (1989) Quim. Nova, 12 (4), p. 318Atvars, Sabadini, (1988) Acta Simposio Latinoamericano de Polimeros (Venezuela), 1, p. 1021Faraggi, Peretz, Rosenthal, Weinraub, (1984) Chem. Phys. Lett., 103, p. 310Ojeda, Amashta, Ochoa, Arbeloa, (1988) J. Chem. Soc., Faraday Trans. 2, 84, p. 1Arbeloa, Arbeloa, Influence of the molecular structure and the nature of the solvent on the absorption and fluorescence characteristics of rhodamines (1989) Chemical Physics, 103, p. 371Arbeloa, Ojeda, Arbeloa, (1988) Chem. Phys. Lett., 148, p. 253Aguilera, Neckers, Aggregation phenomena in xanthene dyes (1989) Accounts of Chemical Research, 22, p. 171Martin, Pardo, Guijarro, Fernandez-Alonso, (1986) J. Mol. Struct, 142, p. 187Lofty, (1985) Photophysical and Photochemical Tools in Polymer Science, Conformation, Dynamics and Morphology, 182, p. 429. , M.A. Winnik, NATO ASI SeriesGuillet, (1985) Photophysical and Photochemical Toals in Polymer Science, Conformation, Dynamics and Morphology, 182, p. 467. , M.A. Winnik, NATO ASI Serie