Chiral Fe nanotubes with both negative Poisson's ratio and Poynting's effect. Atomistic simulation.

Using atomistic calculations, we study the features of uniaxial deformation of nanotubes made of rolled-up thin [0 1 0] plates of Fe cubic crystals. We find that within a certain range of chiral angles these nanotubes have both negative Poisson's ratio and axial strain-induced torsion (reverse Poynting's effect) during tension and compression. The maximum torsion and the minimum value of Poisson's ratio are observed at chiral angles of [Formula: see text] and [Formula: see text], respectively. We show that Young's modulus of the chiral Fe nanotubes increases with a chiral angle. We demonstrate that in the discussed range of nanotube sizes there is a satisfactory correspondence between the results obtained by molecular statics and anisotropic theory of elasticity.