Hydrolysis of Al3+ in Aqueous Solutions: Experiments and Ab Initio Simulations

An experimental and computational study on the hydrolysis of Al3+ in aqueous solutions is here reported. Speciation model formation constants were determined by potentiometric titrations at T = 298.15 K, 0.1 ? I/mol L?1 1 NaCl, NaNO3, NaCl/NaNO3 solutions. The dependence ionic strength reported all media over range 0.1–1.0 mol L?1. Under studied conditions, Al3(OH)45+ Al13(OH)327+ species observed investigated strengths. formed with Cl? together strength. Moreover, aim unveiling molecular structure Al complexes, quantum-mechanical calculations state-of-the-art ab initio dynamics simulations under explicit solvation executed. These computations show, for first time, highly cooperative role played surrounding water molecules neutralising mononuclear systems–such as AlCl2+ AlClOH+–and hydrolytic polynuclear system, Al3(OH)45+.