Correlated Electronic Properties of a Graphene Nanoflake: Coronene

TL;DR

This study investigates the correlated excited states of coronene, a graphene nanoflake, using advanced computational methods to understand electron correlation effects in finite-size graphene analogues.

Contribution

It introduces a new symmetry adaptation scheme and applies the density matrix renormalization group technique to analyze the electronic structure of coronene.

Findings

Electron correlation effects diminish from 1D to higher dimensions.

Symmetry adaptation enhances the analysis of electronic structures.

Finite graphene derivatives exhibit significant electron correlation effects.

Abstract

We report studies of the correlated excited states of coronene and substituted coronene within the Pariser-Parr-Pople (PPP) correlated $\pi$-electron model employing symmetry adapted density matrix renormalization group technique. These polynuclear aromatic hydrocarbons can be considered as graphene nanoflakes. We review their electronic structures utilizing a new symmetry adaptation scheme that exploits electron-hole symmetry, spin-inversion symmetry and end-to-end interchange symmetry. Study of the electronic structures sheds light on the electron correlation effects in these finite-size graphene analogues, which diminishes on going from one-dimensional to higher-dimensional systems, yet is significant within these finite graphene derivatives.