Investigations of energy transfer from some diolefinic laser dyes to Rhodamine 110

Abstract 2,5-Distytyl pyrazine (DSP) and 1,4-bis(β-pyridyl-2-vinyl) benzene (P2VB) laser dyes have been studied with respect to energy transfer to rhodamine 110 (R110) laser dye in methanol and butanol by steady state emission measurements. The Stern–Volmer plots are linear, from which the second order-quenching rate constants of energy transfer ( k ET ) were determined as 9.8×10 12 and 13.4×10 12  mol −1  dm 3  s −1 for DSP–R110, 2.17×10 13 and 2.3×10 13  mol −1  dm 3  s −l for P2VB–R110 in methanol and butanol, respectively. The critical transfer distances ( R 0 ) have been calculated from the emission of donor and absorption spectra of the acceptor using the Forster formula as 41.4 and 41 A for P2VB–R110, 55.5 and 52.7 A for DSP–R110 in the same solvents, respectively. The large values of k ET and R 0 indicate that the dominant mechanism responsible for energy transfer is due to long-range dipole–dipole interaction between excited donor and ground state acceptor molecules.