Na10(Na,Mn)7Mn43(PO4)36: a new synthetic fillowite‐type phosphate

Na₁₀(Na,Mn)₇Mn₄₃(PO₄)₃₆ (sodium manganese phosphate) was synthesized hydrothermally at 873 K and 0.35 GPa. The complex crystal structure is almost identical to that of natural fillowite‐type phosphates and can be described as a hexagonal packing of three types of rods parallel to the c axis. The rods are constituted by an alternation of five‐ to seven‐coordinated Mn sites [average Mn—O = 2.243 (3) Å], of six‐ to nine‐coordinated Na sites [average Na—O = 2.590 (3) Å], of PO₄ tetrahedra [average P—O = 1.548 (3) Å] and of cation vacancies.