Overall the results were in contradiction with the common consensus; that the primary phase transition driving factor is the cell volume alone, as B site substitutions alter the cell volume considerably less than the A site substitutions yet give substantial differences in transition temperature, see figure . B site substitution in LaSr2B2Li7O12 also corresponds to larger increases in tetragonality. This indicates the B site plays a more key structural role in determining tetragonal distortion than the A site . This is logical given the garnet framework polyhedra of corner linked BO6 and XO4 units, as these sites would structurally define the cell more than the interstitial A site.