SOLVATION EFFECTS IN JET-COOLED 7-HYDROXYQUINOLINE

An investigation of the laser-induced fluorescence of jet-cooled 7-hydroxy quinoline and its complexes with water and methanol is presented. The free molecule exhibits two electronic transitions which are due to rotational isomers. The 1:1 complexes present a moderate red spectral < 500 cm-1 shift and a free-molecule-like fluorescence. Higher clusters-with H2O and CH3OH lead to an unusually large red-shift (almost-equal-to 2000 cm-1) and to a strong modification of the vibrational pattern in excitation and dispersed emission spectra. No excited state tautomerization was found in these clusters. The structures of the hydrogen-bonded clusters are discussed in the context of these data.