The energetic preference for cis-Ti[O 2 F 4 ] short-range ordering implies a ground-state structure with 100 % cis-Ti[O 2 F 4 ] coordination, which is consistent with the lowest energy 2 × 2 × 2 structures shown in Fig. , each of which exhibits 100 % ordered cis-Ti[O 2 F 4 ] units. The calculated configurational density of states (cDOS) (Fig. ), however, does not show a clear energy gap above the lowest energy 2 × 2 × 2 structure, and we instead predict multiple low-energy structures that may be expected to be competitive under synthesis . Consequently, as-synthesised samples of ReO 3 -type TiOF 2 are expected to exhibit some degree of partial disorder, while still demonstrating a general preference for local cis-Ti[O 2 F 4 ] coordination.