LANGMUIR-BLODGETT-FILM FORMATION OF A SERIES OF PERIPHERALLY OCTASUBSTITUTED METALLOPHTHALOCYANINES

The behavior at the air/water interface of peripherally octa(pentyloxy)-substituted, nonamphiphilic metallophthalocyanines containing nickel, palladium, and platinum as central metals, respectively, has been studied. For all three, the same value of the limiting area per molecule has been found. Langmuir-layer stability turned out to be strongly dependent on the initial area per molecule given to the molecules upon spreading before compression. Provided that this area was chosen to be appropriately large, LB multilayers could be formed from all three phthalocyanines. As a representative example, LB films of the palladium phthalocyanine were studied by polarization-dependent UV/vis and FTIR spectroscopies as well as small-angle X-ray diffraction. These investigations revealed edge-on orientation of the molecules in well-ordered monolayers.