Dynamics of pull and release of graphene nanoribbons

The pull and release molecular dynamics simulations of graphene nanoribbons (GNR) lead to their length dependent several folded conformations in the ground states at finite temperatures. folding occurs when potential energy stretched GNR is sufficient overcome barriers between flat its conformations. We explore GNRs during as develops intrinsic ripples soon thermal fluctuations are introduced rich mechanical phenomena found even before process starts. Nudged elastic band calculations were performed understand nature minimum paths rippled nanoribbons. kinetic energies show strong oscillatory characters with attenuation amplitudes start end pulling process, but starts becomes weak giving rise small fluctuations. Both thermostatted unthermostatted studied some important observations. Different equivalent continuum models analyzed which can mimic these experiments. It has been that without any rippling be successfully simulated a thin plate model using Hooke’s law does not account for geometric nonlinearities therefore aptly able capture deformations GNR. This relation fails then undergoes through was modeled by introducing nonlinear curve fitting atomistic z-coordinates sinusoidal function. Then three different constitutive relations tried it modeling St. Venant–Kirchhoff materials, assume linear second Piola–Kirchhoff stress tensor Green-St. Venant strain correctly reproduce behavior temperature results also reproduced solving balance equation where thermoelastic subtracted assumed.