The thermos-physical properties allow for a deep understanding of the macroscopic characterization of the mixed fluids, whereas the theoretical study, gives insights into the nanoscopic features of the mixed fluids. The manuscript demonstrates an experimental and computational investigation of intermolecular interactions in a binary system of 1‑butyl‑3-methylimidazolium glutamic acid ([Bmim][Glu]) with 1,2-propanediol. The densities and speeds of the sound of the binary mixture at T = (298.150 to 323.150) K and atmospheric pressures have been measured. Furthermore, the refractive indices of the pure liquids and aforementioned mixture were determined at the same molar fraction but at the temperature range from T = (298.150 to 323.150) K at atmospheric pressure. The obtained experimental values were used to calculate the different thermodynamic parameters. In addition, the quantum mechanical calculation was used to evaluate the electronic properties of the studied binary system.