Molecular Interactions in Dimethyl Carbonate and Adiponitrile Binary System: A Combined Thermodynamic, Spectroscopic, and Molecular Dynamics Study

This study presents a comprehensive investigation of the molecular interactions in the binary system of dimethyl carbonate and adiponitrile (ADN) by integrating thermodynamic measurements, spectroscopic analyses, and molecular dynamics (MD) simulations. Experimental data on density, speed of sound, and refractive index were collected across a temperature range of 293.15 K–318.15 K, revealing significant nonideal mixing behavior, including negative excess molar volumes and positive deviations in speed of sound and refractive index, which intensify with rising temperature due to enhanced intermolecular interactions. MD simulations and spectroscopic evidence (Fourier transform infrared and 1 H NMR) confirm the formation of weak C–H···O and C–H···N hydrogen-bond-like contacts, providing a molecular-level explanation for the observed macroscopic properties. These findings underscore the role of specific dipole–dipole and charge-transfer effects in governing the system’s behavior, offering valuable insights for applications in solvent design and molecular engineering.