Synthesis, optical and structural studies of tetrakis[4-(2′,3′,4′,5′,6′-pentafluorobenzyloxy)benzyloxy]-substituted metallo-phthalocyanines

Metallo-phthalocyanines substituted with four pentafluorobenzyloxy units through benzyloxy-bridges were synthesized from a new phthalonitrile derivative and characterized by spectroscopic methods. The aggregation behaviour of these compounds were investigated in different concentrations of tetrahydrofuran. The effect of solvents on absorption spectra were studied in various organic solvents. Thin films of metallo-phthalocyanines were obtained by using spin coating on 2947 Corning glass substrates. Optical transmittance of thin films was measured using a spectrophotometer in the wavelength range of 300–1000 nm. Results showed that transmittance decreases with the increasing concentration in the ranges corresponding to B and Q absorptions, but the films can still be proposed as optical windows between these regions (∼400–600 nm) due to very low absorbances. The surface morphology of the thin films were investigated by atomic force microscopy. The phthalocyanine molecules grow in stacks of rows rather in the zig–zag or parallel.