# Physisorption of Nucleobases on Graphene

## TL;DR

This study uses first-principles calculations to analyze how different nucleobases interact with graphene, revealing varying binding strengths primarily driven by molecular polarizability, advancing understanding of DNA-carbon nanostructure interactions.

## Contribution

It provides a detailed first-principles analysis of nucleobase-graphene interactions, highlighting the role of polarizability and establishing a foundation for understanding DNA interactions with carbon nanomaterials.

## Key findings

- G has the strongest binding energy, followed by T and C, then A, with U being the weakest.
- Interaction strength varies significantly among nucleobases due to polarizability differences.
- Dispersion forces primarily stabilize nucleobase-graphene interactions.

## Abstract

We report the results of our first-principles investigation on the interaction of the nucleobases adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U) with graphene, carried out within the density functional theory framework, with additional calculations utilizing Hartree--Fock plus second-order Moeller-Plesset perturbation theory. The calculated binding energy of the nucleobases shows the following hierarchy: G > T ~ C ~ A > U, with the equilibrium configuration being very similar for all five of them. Our results clearly demonstrate that the nucleobases exhibit significantly different interaction strengths when physisorbed on graphene. The stabilizing factor in the interaction between the base molecule and graphene sheet is dominated by the molecular polarizability that allows a weakly attractive dispersion force to be induced between them. The present study represents a significant step towards a first-principles understanding of how the base sequence of DNA can affect its interaction with carbon nanotubes, as observed experimentally.