Molecular Dynamics Simulations of the Mechanical Behavior of Amorphous Silica Nanowires
L.P. Dávila, V.J. Leppert, E.M. Bringa
University of California Merced, US
Keywords: molecular dynamics simulations, elastic modulus, stress-strain behavior, amorphous, nanowires
Abstract:Inorganic nanostructures such as nanosprings, nanowires and nanorings are important morphologies of great scientific interest for future technological progress. We have focused our work on the nature and properties of silica nanowires. Nanowires have useful mechanical, electrical and optical properties that could make them useful in small-scale sensing and micro-system applications. We have performed large-scale molecular dynamics (MD) simulations to study the nature and mechanical properties of amorphous silica nanowires. The behavior of non-crystalline silica nanowires is studied using empirical interatomic potentials developed by Feuston and Garofalini. We have applied MD simulations to study the response of the silica nanowires to elevated compressive loads. We have centered our studies on the nanostructural changes occurring in the material and the correlation between the medium-range order (~10 nm), through the characteristic ring distribution of this material. Several glassy nanowires ranging in diameter from ~1.4 nm to ~14 nm are investigated. We derived the elastic modulus of the nanowires from the stress-strain curves and found a distinctive dependence on nanowire diameter. Results are compared with recent experimental findings. This investigation contributes to an understanding of the nature of silica nanowires and their mechanical properties, influencing structure-dependent applications for nanotechnology and materials science.