Surface Structure of V2O3(0001) Revisited

In a recent paper [A. J. Window et al., Phys. Rev. Lett. 107, 016105 (2011)], it was proposed that V2O3(0001) is terminated by the so-called O-3 termination, a reconstruction with a terminating distorted hexagonal oxygen layer. We show that the surface is terminated by vanadyl (V=O) groups instead. This conclusion is based on quantitative low-energy electron diffraction combined with scanning tunneling microscopy, fast atom scattering, and density functional theory employing the Heyd-Scuseria-Ernzerhof functional. New insights into the subsurface sensitivity of ion beam triangulation show that results previously interpreted in favor of the O-3 termination are reconcilable with vanadyl termination as well.