Quantum chemical modeling of the structure and stability of hydrated and sulfated stannic acid complexes

Abstract

Various H₂SnO₃ complexes and their hydrated and sulfated derivatives are calculated within the framework of the cluster approximation with the B3LYP, ωB97XD DFT functionals and the LanL2DZ(Sn), 6-31G**(O,S,H) and DGDZVP basis sets, and taking into account periodic boundary conditions with the PBE functional and the basis of the projector-augmented plane waves PAW. It was found that among the considered hydrated forms, the most energetically preferred are nanostructures in the form of ultrathin bars with a Sn₂O₂ cross section of the composition SnO₂/1.5H₂O and SnO₂/2H₂O. For sulfated complexes, two types of structures can be formed: with H₂SO₄ molecules adsorbed onto the surface of the hydrate shell around SnO₂, and more stable structures with SO₄²⁻ anions directly bound to Sn atoms on the surface of the tin oxide backbone.