In this work, we address the limitations in the performance of using generalised forcefields in molecular dynamics simulations for exotic materials such as graphene. We achievethis through ad hoc molecular dynamics forcefield parameterisation using density functional theory (DFT) calculations of a 1000 atom graphene-oxide (GO) system.
The resulting forcefield parameters display significant differences in the behaviour of GO in complex environments, namely ion behaviour and chaotropic potential. Our results show agreement in water structure as studied by ab initio molecular dynamics (AIMD) and in ion trapping and permeation as observed in experiments.
More generally, it shows that ad hoc forcefield parameterisation of exotic materials is a promising alternative to generalised forcefields. This is fundamental to areas in science where such materials are studied at the interface with biomolecules or in applications such as desalination. Furthermore, this framework provides insight to the dynamics of graphitic materials at timescales of hundreds of nanoseconds, in complex environments that collectively scale to hundreds of thousands of atoms. We believe that this manuscript will be of broad interest with potential impact in numerous application areas.
Full reference: Accurate large scale modelling of graphene oxide: Ion trapping and chaotropic potential at the interface. Mohamed Ali Al-Badri, Paul Smith, Robert C. Sinclair, Khuloud T. al-Jamal & Christian D. Lorenz. Carbon (2020) (2021) 174, 266-275.