A comparative study of density functional and density functional tight binding calculations of defects in graphene

Abstract

The density functional tight binding approach (DFTB) is well adapted for the study of point and line defects in graphene based systems. After briefly reviewing the use of DFTB in this area, we present a comparative study of defect structures, energies and dynamics between DFTB results obtained using the dftb+ code, and density functional results using the localised Gaussian orbital code, AIMPRO. DFTB accurately reproduces structures and energies for a range of point defect structures such as vacancies and Stone-Wales defects in graphene, as well as various unfunctionalised and hydroxylated graphene sheet edges. Migration barriers for the vacancy and Stone-Wales defect formation barriers are accurately reproduced using a nudged elastic band approach. Finally we explore the potential for dynamic defect simulations using DFTB, taking as an example electron irradiation damage in graphene.

References in corpus (5)

• Relativistic separable dual-space Gaussian Pseudopotentials from H to Rn
• Stone-Wales--type transformations in carbon nanostructures driven by electron irradiation
• Shaping single walled nanotubes
• Low energy graphene edge termination via small diameter nanotube formation
• Ripple edge engineering of graphene nanoribbons

Cited by in corpus (8)

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• Performance Analysis of Boron Nitride Embedded Armchair Graphene Nanoribbon MOSFET with Stone Wales Defects
• Point defect formation energies in graphene from diffusion quantum Monte Carlo and density functional theory
• Mechanical Properties of Pristine and Defective Carbon-Phosphide Monolayers: A Density Functional Tight-Binding Study
• Interplay between edge states and simple bulk defects in graphene nanoribbons