Preparation and characterization of molecular-material thin films containing diaqua tetrabenzo (b,f,j,n) {1,5,9,13} tetraazacyclohexadecine copper (II) and nickel (II) bisanthraflavates

Semiconducting molecular-material thin films of tetrabenzo (b,f,j,n) {1,5,9,13} tetraazacyclohexadecine copper (II) and nickel (II) bisanthraflavates have been prepared by using vacuum thermal evaporation on corning glass substrates and crystalline silicon wafers. The obtained films were characterized by infrared spectroscopy (FTIR), atomic force microscopy (AFM), ultraviolet-visible (UV-Vis) spectroscopy and ellipsometry. The values of the electric current as a function of temperature are always higher for the complexes with nickel than for those with copper. Charge transfer for these complexes shows preferential conducting paths that can be attributed to the hydrogen bonds of the anthraflavate anions. Electric conductivity values found for thin films are higher than for pellets made of the same molecular materials.