Quantum chemical insight on the uranyl benzoates association with cetylpyridinium

The possibility of analytical determination of the uranyl cation UO22+ (taken in the form of the complex uranyl benzoate anion) by using the potentiometric titration technique has been theoretically investigated via DFT modeling and OPLS-AA force field molecular dynamics. The results of the quantum chemical calculations indicate that, among the benchmarked candidate carboxylate anions, the benzoate anion is seemingly characterized by the optimum combination of the binding properties for complexation with the uranyl cation: it shows a relatively high binding to the uranyl cation and, simultaneously, a high binding of the formed uranyl benzoate anion to the cetylpyridinium cation used as a titrant. Moreover, among the considered uranyl-carboxylate anions, the uranyl benzoate anion has been found to be the most lipophilic, which characterizes this form as the most suitable for uranyl determination.