Molecular Interactions in Tetrachloroethylene-Cyclohexanone Binary Mixtures: Acoustical and FTIR Investigations at Different Temperatures

The speed of sound (U), density (ρ), and viscosity (η) of binary liquid mixtures of tetrachloroethylene with cyclohexanone, as well as their pure components, were measured across varying mole fractions at four temperatures: 303.15 K, 308.15 K, 313.15 K, and 318.15 K. These experimentally determined physical properties were subsequently used to calculate thermo-acoustic parameters, including excess molar volume (V^E), excess free length (L_f^E), excess Gibbs free energy (ΔG^E), and excess enthalpy (H^E). The observed trends in these parameters were analysed to understand the nature and strength of intermolecular interactions present within the binary mixtures. Additionally, the experimentally measured speed of sound was compared with values predicted by established theoretical models to evaluate their applicability to the system. The models that showed the closest agreement with the experimental data highlighted the presence of specific molecular interactions, such as hydrogen bonding and dipole-dipole interactions, between the components. Further, Fourier Transform Infrared (FTIR) spectroscopy provided detailed insights into the molecular interactions, confirming the presence of structural and chemical effects influencing the thermophysical behaviour of the mixtures. The study offers a comprehensive analysis of molecular interactions in tetrachloroethylene-cyclohexanone mixtures across a range of temperatures.