These results show that the lithium intercalation energy for ReO 3 -type TiOF 2 is sensitive to the precise arrangement of oxygen and fluorine atoms within the host structure, with the mean intercalation energy shifting by > 1.5 eV between the fully ordered all-cisTi[O 2 F 4 ] structure and the 4 × 4 × 4 special quasirandom structure considered here. In general, as the anion substructure becomes more configurationally disordered, the in-intercalation energy / eV FIG. 12. Effect of changing O/F substructure on lithium intercalation energies into cubic TiOF2. Data are shown as raincloud plots for three exemplar structures: (top) the fully-ordered all-cisTi[O2F4] structure; (middle) a 4×4×4 supercell genetic-algorithm-predicted structure (GA structure 4); (bottom) the 4×4×4-supercell special quasi-random structure (bottom). For each dataset, the points show individual calculated intercalation and the solid distribution shows a kernel density estimate of the distribution of intercalation energies. Error bars show the 95 % compatibility interval for the estimated mean of each dataset, obtained by bootstrap resampling of the original data .