Elucidating the volumetric and acoustic characteristics of alkanediols: empirical insights into molecular interactions

The densities and speed of sound in binary mixtures consisting of water with 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, and 1,3-butanediol were extensively measured across the entire composition spectrum, ranging from 288.15 K to 323.15 K with 5 K intervals. Utilizing the gathered experimental data, excess properties including excess molar volume, excess isentropic compressibility, excess molar isentropic compressibility, excess speed of sound, excess isobaric thermal expansion, excess acoustic impedance and excess free length was computed for these examined mixtures. The outcomes were evaluated based on molecular interactions and structural impacts. In the investigation of excess molar volume, it was observed that smaller water molecules tend to form more efficient arrangements when packing with larger diols. In order to investigate molecular electronic properties, Density Functional Theory (DFT) calculations were also carried out. The parameters that were obtained confirmed the existence of intermolecular interactions between water and diol molecules.