Solvent structure. The use of internal pressure and cohesive energy density to examine contributions to solvent-solvent interactions

Abstract

Internal pressures, (∂U/∂V)T, have been obtained at 25° for the solvents dimethyl sulphoxide, propylene carbonate, formamide, dimethylformamide, acetonitrile, methanol and hexamethyl-phosphoramide by measurement of the thermal pressure coefficients. Data in the literature suggest that values of the internal pressure and the cohesive energy density, (ΔU/V_m), are similar for a non-polar solvent. The observed divergence of the two properties in the polar solvents under investigation is discussed in terms of the nature of the solvent-solvent interactions.