Mechanical Properties and Fracture Dynamics of Silicene Membranes

TL;DR

This paper investigates the mechanical properties and fracture behavior of silicene membranes using computational methods, revealing how edge structures and temperature influence their fracture patterns and stability.

Contribution

It provides new insights into silicene's mechanical response, including elastic constants, fracture mechanisms, and edge effects, through detailed simulations.

Findings

Silicene exhibits distinct fracture patterns based on edge morphology.

Temperature affects stress distribution and unbuckling mechanisms.

Elastic constants of silicene are characterized through simulations.

Abstract

As graphene became one of the most important materials today, there is a renewed interest on others similar structures. One example is silicene, the silicon analogue of graphene. It share some the remarkable graphene properties, such as the Dirac cone, but presents some distinct ones, such as a pronounced structural buckling. We have investigated, through density functional based tight-binding (DFTB), as well as reactive molecular dynamics (using ReaxFF), the mechanical properties of suspended single-layer silicene. We calculated the elastic constants, analyzed the fracture patterns and edge reconstructions. We also addressed the stress distributions, unbuckling mechanisms and the fracture dependence on the temperature. We analysed the differences due to distinct edge morphologies, namely zigzag and armchair.