Calculations of concentration dependences of chemical shifts for acrylamide in water-DMSO mixed solvent

The lattice model of associated solutions was used to calculate the concentration dependences of the chemical shifts of C-13 magnetic nuclei in the acrylamide molecule in water-DMSO solvent. Each pair of bonds between the acrylamide group containing a magnetic nucleus and the neighboring solvent molecule was assumed to additively contribute to the change in the chemical shift of the nucleus in question. The new approach affords the same accuracy in describing the experimental data at any ratios of the solution components. It was shown that the chemical shifts and the excess heat of mixing of the water-DMSO binary solution can be simultaneously described using the same set of energy parameters of the model. The model makes it possible to employ experimental data on chemical shifts for studying intermolecular interactions in solutions.