Multilayer silicene: Structure, electronics, and mechanical property

Abstract

Abstract Herein, we performed first-principle calculations and classical molecular dynamics simulations to study geometry optimizations, band structures, and mechanical properties of differently stacked multilayer silicenes. Several local energy minima have been identified as metastable conformations with different stacking modes and layer numbers. Bandstructure of the low buckled AA bilayer silicene optimized with SCAN + rvv10 presents semiconducting behavior with a bandgap of 0.4419 eV. Young’s modulus of multilayer silicene shows low dependence on layer number or stacking mode. Whereas, fracture stress and strain are sensitive to the number of layers, specific stacking modes, and chiralities. Furthermore, bending moduli of multilayer silicenes (e.g., 0.44 eV for monolayer silicene) are even lower than that of graphene, which may attribute to the flexibility of bond angle.