In contrast, a comparison of the Zr and Hf samples suggest an influence of B site doping, and that this effect requires only a very minimal difference in ionic radius between substituents. Further support for the effect of B site doping is shown by comparing further samples substituted on this site, such as the Ce-doped LLZO and LaSr2B2Li7O12 (B = Nb, Ta) phase. These showed clear differences in transition temperature, at ~325 -425 °C and 800 -900°C respectively (see table ), with the lower transition temperature corresponding to the presence of larger cations in the B site. In line with the transition temperature changes, this corresponded to similar (Ce doped LLZO) and increased (LaSr2B2Li7O12, B = Nb, Ta) degrees of tetragonality.