In this work, we propose a new auxetic (negative Poisson's ratio values) structure, based on a γ-graphyne structure, here named AγGstructure. Graphynes are 2D carbon allotropes with phenylic rings connected by acetylenic groups. The AγG structural/mechanical and electronic properties, as well as its thermal stability, were investigated using classical reactive and quantum molecular dynamics simulations. We found that AγG has a large bandgap of 2.48 eV and is thermally stable at a large range of temperatures. It presents a Young's modulus that is an order of magnitude smaller than that of graphene or γ-graphyne. The classical and quantum results are consistent and validate that the AγG is auxetic, both when isolated (vacuum) and when deposited on a copper substrate. We believe that this is the densest auxetic structure belonging to the graphyne-like families.
@article{arxiv.2109.04647,
title = {Auxetic properties of a newly proposed $\gamma$-graphyne-like material},
author = {Ricardo Paupitz and Tales J. da Silva and Marilia J. Caldas and Douglas S. Galvão and Alexandre F. Fonseca},
journal= {arXiv preprint arXiv:2109.04647},
year = {2022}
}