Study of the effect of hydration on the tensile strength of a silica nanotube

Molecular dynamics simulations using quantum mechanical potentials have been performed to study the interaction of water with silica. The water-water and water-silica interactions were determined at the ab initio coupled cluster and MBPT(2) levels of theory and the resulting forces and reaction mechanisms encoded into a transfer Hamiltonian. Using forces from the rapid evaluation of the transfer Hamiltonian, two prototypical systems, consisting of an (SiO ₂)₁₀ ring and a 108 atom silica nanorod, were fractured in the presence of water. It was found that inclusion of water caused a reduction in tensile strength of both systems and that the water dimer, as suggested by ab initio calculations, is the most effective mediator of Si-O bond rupture.