Exploring the Molecular Interactions of 1,3-Dimethylimidazolium Methyl Sulfate Ionic Liquid in Aqueous and Aqueous <scp>l</scp>-Alanine Solutions at Various Temperatures

The present study employed volumetric and compressibility methods to investigate the intermolecular interactions of 1,3-dimethylimidazolium methyl sulfate, i.e., [MMIm][MeSO4] ionic liquid in both aqueous and aqueous l-alanine solutions. Density (ρ) and sound velocity (c) for [MMIm][MeSO4] in two different systems such as the binary system ([MMIm][MeSO4] in water) and the ternary system ([MMIm][MeSO4] in 0.05 mol kg–1 aqueous l-alanine solution) were measured within a temperature range of 288.15–318.15 K at intervals of 5 K over the concentration range of 0.03–0.15 mol kg–1. We calculated various parameters such as the apparent molar volume of solute (Vϕ), the limiting apparent molar volume of solute (Vϕο), the experimental slope (Sv), the isobaric thermal expansion coefficient (α), the transfer limiting apparent molar volume of solute (ΔtrVϕ0), the isentropic compression of solution(κS), the apparent molar isentropic compression of solute (KS,ϕ), the partial molar isentropic compression of solute (KS,ϕ0), the transfer partial molar isentropic compression of solute (ΔtrKS,φ0), and Hepler’s constant (∂2Vϕ0/∂T2) by using the experimental ρ and c data. The outcomes are elucidated in terms of interactions between the solute–solute and solute–solvent in the studied systems.