Auxetic properties of a newly proposed γ-graphyne-like material

Abstract

A new auxetic (negative Poisson's ratio values) structure based on a γ-graphyne structure, here named AγG structure, is proposed. The AγG structural/mechanical and electronic properties, as well as its thermal stability, were investigated using classical reactive and quantum molecular dynamics simulations. AγG is shown to have a bandgap larger than 1.6 eV and be thermally stable at a large range of temperatures. The classical and quantum results 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.