Anab initiocalculation of the ideal tensile strength of β-silicon nitride

Abstract

In this study, the ideal strength of \ensuremath{\beta}-silicon nitride was calculated using a first-principles molecular dynamics method. The stress-strain curve of \ensuremath{\beta}-silicon nitride was calculated from simulations of uniaxial extension in the [100] and [001] axial directions, and an ideal tensile strength of \ensuremath{\sim}72.2 and \ensuremath{\sim}75.0 GPa, respectively, was obtained. In addition, the elastic constants were determined, along the two principle axial directions, [100] and [001], and values of \ensuremath{\sim}559 and \ensuremath{\sim}403 GPa, respectively, were obtained. The elastic constant results were found to be in reasonable agreement with existing data.