ReO 3 -type TiOF has previously been as a potential lithium-ion electrode material Our results indicate that ReO 3 -type TiOF 2 exhibits a specific short-range anion ordering consisting of preferential cis-TiO 2 F 4 titanium coordination, which gives rise to correlated disorder at longer length-scales. Our analysis of the relative energies of different anion configurations shows that there are a large number of low-energy anion configurations that are expected to be competitive under synthesis conditions (Fig. ), indicating that the precise anion configuration in ReO 3 -type TiOF 2 might depend experiment simulated FIG. . Experimental (solid line) and simulated (dashed line) 19 F MAS (64 kHz) NMR spectra of ReO3-type TiOF2 (GA-predicted structure 4).