Density functional aspects and thermodynamic evaluation of sodium dodecyl sulphate in aqueous tartrazine

Abstract Sodium dodecyl sulphate (SDS) and tartrazine (TAR) are involved in manifold industrial and medicinal applications. Under such a fascination, this work describes the conjoint experimental-theoretical investigation of a binary mixture containing SDS in aqueous TAR (0.001 M). The study involves the evaluation of some primary thermodynamic parameters due to SDS-TAR micellization and a special focus on computational density functional theory (DFT) approach using water as solvent under 631-g(d,p) as basis set and B3LYP as the respective functional. Structures of both the SDS and TAR were separately optimized first, followed by the calculation of their mixture under the same quantum chemical theory. After confirming the absence of imaginary frequency in the frequency calculation of each set further theoretical calculations were done to get the respective molecular orbital energies and several other descriptors to reveal the difference of chemical behaviour in relation to pre- and post-micellization processes. The study shows remarkable agreement between DFT and experimental outcomes.