Skip to main content
Fig. 3 | Nano Convergence

Fig. 3

From: A perspective on auxetic nanomaterials

Fig. 3

(Reprinted (adapted) with permission from Jiang and Park [28]. Copyright (2016) American Chemical Society)

Poisson’s ratio for graphene from Set I. a Strain dependence for Poisson’s ratio. Inset displays the strain–strain relation for graphene with width 29.51 Å, in which graphene expands in the y-direction when it is stretched in the x-direction by strain smaller than \(\epsilon _c=0.005\), indicating the NPR effect. b The strain dependence for the z positions of two atoms in the peak (valley) of the warped edge in graphene. Data are fitted to functions \(z=\pm b_0\sin [\theta _0(1-\epsilon /\epsilon _c)]\) with constraint \(b_0=z_0/\sin \theta _0\). Inset displays these two atoms; i.e. the atom on the peak (red arrow) and valley (blue arrow) of the warped edge. Both atoms fall into the graphene plane for strain larger than \(\epsilon _c\). c Width dependence for the Poisson’s ratio. Inset shows the critical strain in graphene ribbons of different width

Back to article page