Short-Range Order in VI.

We present a detailed investigation of the crystal structure of VI, a two-dimensional van der Waals material of interest for studies of low-dimensional magnetism. As opposed to the average crystal structure that features 3̅ symmetry of the unit cell, our Raman scattering and X-ray atomic pair distribution function analysis supported by density functional theory calculations point to the coexistence of short-range ordered 3̅1 and long-range ordered 3̅ phases. The highest-intensity peak, , exhibits a moderate asymmetry that might be traced back to the spin-phonon interactions, as in the case of CrI.