Na7 Fe4 (P2 O7)4 P O4

Fe₄Na₇O₃₂P₉

Rochere, M.Kahn, A.d'Yvoire, F.Bretey, E.

Materials Research Bulletin (1985) 20, 27-34

a=14.105Å   b=14.105Å   c=6.378Å

α=90°   β=90°   γ=90°