Monolayers and Langmuir-Blodgett films of (phthalocyaninato)(tetra-4-pyridylporphyrinato) double-decker heterocomplex

Monolayers of a sandwich-type heterocomplex Ce(TPyP)(Pc) with porphyrin-pht halocyanine ligands and its mixtures with stearic acid (SA) have been inves tigated at the air-water interface. The limiting molecular area for the com plex in mixed monolayers is almost independent on the molar fractions of SA . However, SA molecules effectively disperse the aggregates of the Ce(TPyP) (Pc) molecules according to the direct observation by Brewster angle micros copy, and the collapse processes are dependent on the molar ratios of the c omplex and SA. The monolayer of the complex mixed with SA was successfully deposited on hydrophobic substrates by Langmuir-Blodgett (LB) method. The U V-vis absorption peaks of LB films are red shifted compared with those in s olution, indicating the formation of J-aggregates. The macrocycle rings of the complex in LB films were evaluated to be ca, 30 degrees with respect to the substrate. A rather small distance between two layers was measured. Ba sed on all these considerations, a schematic arrangement of molecules in LB films was suggested. (C) 2000 Elsevier Science B.V. All rights reserved.