Local chiral-symmetry breaking in globally centrosymmetric crystals.

A thorough tensor analysis of the Bragg-forbidden reflection (00.3)(h) in corundum systems having a global center of inversion, such as V2O3 and alpha-Fe2O3, shows that anomalous x-ray resonant diffraction can access chiral properties related to the dipole-quadrupole (E1-E2) channel via an interference with the pure quadrupole-quadrupole (E2-E2) process. This is also confirmed by independent ab initio numerical simulations. In such a way, it becomes possible to detect chiral quantities in systems where dichroic absorption techniques are ineffective.