INTRAMOLECULAR ENERGY-TRANSFER IN BICHROMOPHORIC DIESTERS CONTAINING ANTHRACENE AND NAPHTHALENE GROUPS SEPARATED BY DIFFERENT NUMBERS OF METHYLENE SPACERS

Steady state fluorescence has been used to study the efficiency of nonradiative singlet energy transfer from naphthalene to anthracene in naph-COO-(CH2)m-OOC-anth for m of 2-6. A theoretical analysis has also been performed, using the rotational isomeric state model, of the conformations of these molecules. The experiments clearly demonstrate the presence of nonradiative singlet energy transfer in the bichromophoric compounds, with an efficiency that depends on the solvent and on m. The combination of the experiments and the theoretical analysis establishes that the Forster radius for this system is 1,6 +/- 0,2 nm.