Quantum chemical calculations for the hydration of model silica modified by aliphatic amines

Abstract

Various basis sets and methods for quantum-chemical calculations are analyzed, and the effect of the number of diffusion and polarization functions on geometry and energy characteristics of systems that simulate the surface of silica modified by aliphatic amines is studied. The contribution from correlation effects and the superposition error of the basis set to the values of the energy characteristics of the hydration of model objects is evaluated. A section of an aminosilica surface was hydrated in simulation. Conclusions as to the existence of arched structures on the surface of aminosilica that include amino and silanol groups are confirmed.