Density dependence of elastic properties of graphynes

Graphyne is a two-dimensional carbon allotrope of graphene. Its structure composed aromatic rings and/or carbon-carbon bonds connected by one or more acetylene chains. As some graphynes present the most excellent properties graphene and non-null bandgap, they have been extensively studied. Recently, Kanegae Fonseca reported calculations four elastic 70 graphynes, ten members seven families [Carbon Trends 7, 100152 (2022)]. They showed that chain length dependence these can be simply modelled serial association springs. Here, based on those results, we density show moduli, $E$, graphyne are less dependent density, $\rho$, than porous cellular materials with an exponent $E \sim \rho^{n}$, smaller 2. We discuss results in terms shape pores structures.