Monolayer properties of an amphiphilic copper (II) complex at the air–water interface

The monolayer of amphiphilic Cu(NO3)2(dps), (2,2′-dipyridylstearylamine)dinitratocopper (II), was studied at the air-water interface. Cu(NO3)2(dps) was synthesized from substitution of stearyl chloride with dipyridylamine followed by coordination of the ligand with Cu(NO3)2·3H2O. The Cu(NO3)2(dps) monolayer was stable up to ca. 20 mN/m of surface pressure and showed condensed phase. The surface pressure-area isotherms were exactly reproducible from the second compression–expansion cycle. The optical image of the monolayer was monitored by Brewster angle microscopy (BAM). Homogeneous monolayer phase was estimated from the BAM images. The Cu(NO3)2(dps) monolayer was transferred on calcium fluoride substrate as Y-type and the chemical structure of the Langmuir–Blodgett film was determined by FT-IR spectroscopy.