The excitation dependence of the luminescence and MCPL of Ru(bpy) 2+3 in rigid solutions

Abstract

Luminescence and magnetic circular polarization of luminescence (MCPL) of Ru(bpy) 2+ 3 in poly(vinyl-alcohol) and 4:1 ethanol/methanol solid solutions show a significant dependence on excitation wavelength through the wavelength region that shows an anomaly in the excitation polarization ratio. This is interpreted as preferential excitation of ions with various degrees of distortion in the ground state, due to asymmetrical solvent/counterion interactions. The MCPL in rigid glasses is not constant across the emission band and has a complex temperature dependence. This parallels behavior observed with doped single crystals. The temperature dependence of the MCPL above 10 K, is characteristic of a number of (degenerate) E emitting levels and similar behavior is observed in anisotropic and inhomogeneous systems where D 3 ground state symmetry is broken. Assignments of the luminescent states are discussed.