Theoretical Description of Mixed Film Formation at the Air/Water Interface: Carboxylic Acids-Alcohols.

The thermodynamic parameters of formation and clusterization of aliphatic alcohols C HOH and carboxylic acids C HCOOH ( = 6-16) are calculated using the quantum-chemical semiempirical PM3 method. Four types of dimers are constructed in two directions of the spread monolayer comprising the most energetically advantageous monomer structures. The hydrophobic chains of alcohol and carboxylic acid molecules in the regarded dimers are found to be tilted within 12° to the normal of the spread monolayer.