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

A new auxetic (negative Poisson's ratio values) structure based on a gamma-graphyne structure, here named A gamma G structure, is proposed. The A gamma G structural/mechanical and electronic properties, as well as its thermal stability, were investigated using classical reactive and quantum molecular dynamics simulations. A gamma G 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 A gamma G 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.

Automated summary

A new auxetic structure called A gamma G, based on a gamma-graphyne structure, is proposed and investigated for its structural, mechanical, electronic properties, and thermal stability using classical and quantum molecular dynamics simulations. The results show that A gamma G has a bandgap larger than 1.6 eV and remains thermally stable at a wide range of temperatures. Both classical and quantum simulations confirm the auxetic behavior of A gamma G when isolated or deposited on a copper substrate. This study suggests that A gamma G is one of the densest auxetic structures among the graphyne-like families.