Aggregation induced reabsorption of phenanthrene microcrystallites in ultrathin Langmuir-Blodgett films

This article reports the formation of Langmuir-Blodgett films of non-amphiphilic phenanthrene mixed with a fatty acid. The behavior of the phenanthrene molecules at the air-water interface reveals a repulsive type of interaction between the phenanthrene and the fatty acid molecules resulting in the formation of aggregates of phenanthrene. Spectroscopic studies reveal broadening of the absorption spectra and exceptionally large shifts in the emission spectra that may be attributed to the formation of microcrystalline domains. Scanning electron microscopy confirms the existence of microcrystalline domains in the LB films.