Langmuir-Blodgett films of a modified tetraphenylporphyrin

Langmuir-Blodgett (LB) films of 5,10,15,20-tetrakis-[4-(1-Heptyloxy)phenyl]porphyrin (H2THOPP) in a 1/4 molar ratio with arachidic acid have been deposited onto quartz and silver substrates at the surface pressure of 25 nnN/m. A detailed analysis of the Langmuir isotherms is presented. Optical absorption spectra show aggregation of the porphyrins in the LB film. The deposited layers have been characterised by Reflectance Anisotropy Spectroscopy (RAS), showing a large anisotropy signal measured in the Soret band energy region.