Synthesis and crystal structure of a new alluaudite-like iron phosphate Na2CaMnFe(PO4)3

Abstract

A new iron phosphate, disodium calcium manganese(II) iron(III) tris(phosphate), Na2CaMnFe(PO4)3, has been synthesized as single crystals by the flux technique. This compound crystallizes in the monoclinic space group C2/c. The structure belongs to the alluaudite structural type and thus, it obeys the X(2)X(1)M(1)M(2)2(PO4)3 general formula. Both the X(2) and X(1) sites are fully occupied by sodium, while M(1) is occupied by calcium and M(2) exhibits a statistical distribution of iron and manganese.