Hydrogen bonding in neat aliphatic alcohols: The Gibbs free energy of self-association and molar fraction of monomer

Abstract

The magnitudes of the Gibbs free energies of self-association for several primary aliphatic alcohols at 298 K are calculated. The fraction of monomeric molecules in bulk alcohols is determined. We started from the experimental data on the Gibbs free energies of vaporization of alcohols, and quantified the contributions from three types of solvation effects: non-specific van der Waals interactions, solvophobic effects, and hydrogen-bonding processes (self-association) using an extrathermodynamic approach. Calculated values for monomer fractions are compared and found to be in general agreement with the results obtained from various association models: CPA, NRHB, sPC-SAFT, and other data reported in literature. The influence of hydrogen bond cooperativity on the process of self-association is shown. © 2012 Elsevier B.V. All rights reserved.