EFFECT OF MATRIX COMPOUND ON THE DIMERIZATION OF SULPHORHODAMINE-B INLANGMUIR-BLODGETT-FILMS

Time-resolved fluorescence decay curves of N-(Lissamine rhodamine B su lfonyl)dipalmitoyl-phosphatidyl choline (SR) in Langmuir-Blodgett (LB) monolayers have been measured in dipalmitoylphosphatidic acid (DPPA), dipalmitoylphosphatidylcholine (DPPC) and stearylamine (STAM) matrice s. The fluorescence of dye monomers is efficiently quenched by energy transfer to dimers. The existence of two kinds of dimers was observed. Sandwich-type J dimers were found in DPPC matrix, whereas H dimers wi th oblique geometry seem to prevail in DPPA and STAM matrices.