Continuum Modeling with Functional Lennard-Jones Parameters for DNA-Graphene Interactions

Abstract

Carbon nanostructures are of particular interest as platforms for molecular storage and adsorption. In this paper, the adsorption of a single stranded DNA molecule onto a graphene sheet is considered. Even though DNA molecules are complicated heterogeneous structures comprising several types of atoms, it is found that the repeated patterns within the DNA molecules enable the use of a continuum approach to model the DNA-graphene sheet interaction. Here, a model is proposed such that the heterogeneity across the DNA molecule is captured by interaction functions, which are used to replace the attractive and repulsive constants in the Lennard-Jones potential. Result from this new model shows better agreement to molecular dynamics simulations compared to the traditional continuum approach where atoms on the DNA are averaged evenly across the molecule. Finally, the paper comments on the model, its parameters, and suggests ways for improvement.