“…Our recent investigation of iron monophosphates belonging to the A 3 PO 4 -M 3 (PO 4 ) 2 -FePO 4 with A and M are an alkali metal and a divalent cations, respectively, have led to synthesis of several compounds using either a flux method or a solid state reaction techniques [1][2][3][4][5][6][7][8]. The structures of the synthesized compounds consists of bi-or three-dimensional frameworks, in which iron can adopt various environment polyhedra: tetrahedron [2,5], trigonal bipyramid [3,5] or octahedron [1,5,8].…”