Simulation Studies of Mechanical Properties of Novel Silica Nano-structures

Advances in nanotechnology and the importance of silica as a technological material continue to stimulate computational study of the properties of possible novel silica nanostructures. Thus we have done classical molecular dynamics (MD) and multi-scale quantum mechanical (QM/MD) simulation studies of the mechanical properties of single-wall and multi-wall silica nano-rods of varying dimensions. Such nano-rods have been predicted by Mallik \textit{et al.} to be unusually strong in tensile failure. Here we compare failure mechanisms of such nano-rods under tension, compression, and bending. The concurrent multi-scale QM/MD studies use the general PUPIL system (Torras \textit{et al.}). In this case, PUPIL provides automated interoperation of the MNDO Transfer Hamiltonian QM code (Taylor \textit{et al.}) and a locally written MD code. Embedding of the QM-forces domain is via the scheme of Mallik \textit{et al.} Work supported by NSF ITR award DMR-0325553.