Diffraction from twisted nanowires: helicity revealed by anisotropy

The helical nature of twisted nanowires is studied by simulated X-ray diffraction. It is shown that this helicity is revealed by the anisotropy, which can be both an elastic anisotropy, through the warping displacement generated by torsion, or a shape anisotropy of the cross section. To support the analytical calculations, based on the kinematic theory of diffraction by helices, atomistic simulations of copper nanowires are performed.