Interfacial behaviour of brominated fullerene (C60Br24) and stearic acid mixed Langmuir films at air–water interface

The interfacial properties of the spread Langmuir films of C₆₀Br₂₄ and stearic acid have been studied at air–water interface by measuring their surface pressure–area isotherms. Monolayer studies on C₆₀Br₂₄ suggest a strong aggregation at air–water interface which corroborated the ab initio electron density calculations. The mixed films were found to be immiscible and non-ideal with an exception of X_C60Br24=0.5 which is the composition of greater stability. The interaction between C₆₀Br₂₄ and stearic acid results in the lowering of surface pressure withstood by stearic acid and hence the decrease in compressibility with the increasing X_C60Br24, thereby indicating the domination of C₆₀Br₂₄ characteristics in the mixed monolayers.