Solution Properties of Folic Acid/Nicotinic Acid in Aqueous 1-Butyl-3-methylimidazolium-chloride Media at Discrete Concentrations and Temperatures: A Thermodynamic, Computational, and Spectroscopic Study

In the current study, physicochemical properties of folic acid/nicotinic acid have been estimated in aqueous solutions of ionic liquid, 1-butyl-3-methylimidazolium chloride, [C4mim][Cl] (0.05, 0.10, and 0.15 mol kg–1) at different temperatures (293.15–313.15) K and pressure, P = 0.1 MPa. The density data have been employed for the estimation of apparent molar volume (Vϕ), partial molar volume (Voϕ), partial molar volume of transfer (Vϕ,tro), partial molar expansibility (Eϕo), Hepler's constant (∂2Vϕo∂T2)P, and apparent specific volume. The sound velocity data have been utilized for the estimation of apparent molar isentropic compression (Kϕ,s), partial molar isentropic compression (Kϕ,so), hydration number (nH), and partial molar isentropic compression of transfer (Kϕ,s,tro). The viscosity data have been fitted into the Jones-Dole expression for the estimation of A and B viscosity constraints and (dBdT)values along with activation parameters of viscous flow (Δμ10, Δμ20, ΔH20, and TΔS20). Furthermore, the UV–vis, 13C NMR spectral analysis, and DFT calculations have been carried out for the determination of various interactions prevailing in the investigated systems. It has been established that there is an existence of strong vitamin-[C4mim][Cl] interactions in the prepared systems which in turn advances with escalation in concentration of vitamins as well as aqueous [C4mim][Cl] solvent systems.