CHARACTERIZATION OF PHTHALOCYANINE LANGMUIR-BLODGETT-FILMS BY OPTICALDICHROISM AND RESONANCE RAMAN-SCATTERING

In this Paper we report optical dichroism and polarized resonance Rama n scattering measurements on Langmuir-Blodgett layers of tetra tertiar y butyl monosulphonic acid of phthalocyanine (tBPcSA). These measureme nts were performed to determine molecular alignment and local ordering in our samples, using surface enhanced optical and Raman spectroscopy . Thus our L-B layers were deposited on rough thin (50 Angstrom) Ag is land films. We found that the surface enhancement effects dominated th e optical behaviour of our samples, making it more difficult to extrac t the desired information on molecular orientation. At the same time, we found that tBPcSA L-B layers can be a good system to study resonanc e effects and to test the reliability of the structural information ob tainable by optical spectroscopic techniques.