To complete this section, we feel the fits to the models for the predicted compounds Na 3 Ca 18 Fe(PO 4 ) 14 , Na 7 Mg 7 Fe 5 (PO 4 ) 12 , Mn 7 (P 2 O 7 ) 4 , and K 4 TiSn 3 (PO 5 ) 4 are so poor that they cannot provide any evidence of formation of a new material, in such a complex composition space with a large number of possible candidate phases. We will not explore these particular compounds further.