Temperature and medium effects on the photophysical properties of –Re(CO)3(2,2′-bipyridine) pendant chromophores coordinated to a poly(4-vinylpyridine) backbone

Abstract

Solvent and temperature effects on the photophysical properties of the polymer {[(vpy)₂-vpyRe(CO)₃2,2′-bipyridine] CF₃SO₃}_n∼200 and the related monomer CF₃SO₃[pyRe(CO)₃2,2′-bipyridine] were investigated in solution by flash photolysis at 337, 351 and 355 nm and by steady state irradiations. MLCT excited states in the polymer undergo a more efficient annihilation than in the monomer. Differences between the polymer and the monomer photophysical behavior are rationalized in terms of solvent and thermal effects on the transition between rigid rod and coil structures of the Re(I)-polymer.