Molecular dynamics study on the bending rigidity of graphene nanoribbons

The electromechanical responses of a graphene nanoribbon, such as its ripple magnitude, bending rigidity and effective spring constant, were investigated via classical molecular dynamics simulations and the elastic plate theory with a view to future engineering applications of graphene-nanoribbon-based nanoelectromechanical devices. While the bending rigidity was low for large ripples, it was high for very small ripples. However, on most ripple scales, the values of the bending rigidity remained constant around 2.3 eV. The bending rigidity gradually increased from about 1.2 to 2.37 eV with increasing deflection, after that, the bending rigidity slightly decreased to 2.29 eV with further increases in deflection, and finally rapidly increased to 2.93 eV with increasing deflection until the breaking point. The effective spring constant increased to 0.36 N/m with increasing applied force and deflection, in the linear elastic region it remained below ∼0.25 N/m.