CRYSTAL-STRUCTURE OF K4MNMO4O15 - A PARENT COMPOUND OF A NEW ISOSTRUCTURAL SERIES OF COMPLEX OXIDES K4M2+MO4O15 (M2+=MN, MG, CO, CD)

The structure of K4MnMo4O15 was solved from single-crystal X-ray diffr action data (a = 10.372, c = 8.160 Angstrom, Z = 2, space group P (3) over bar, 2152 reflections R = 0.039). The structure is of new, glaser ite-like, type. A characteristic and original feature of the structure is a Mn(II)O-6 octahedron with six MoO4 tetrahedra attached to it by their vertices; the octahedron is linked with a MoO6 octahedron by a c ommon face. The MoO4 tetrahedra bridge the octahedral dimers with each other, forming lacy layers with potassium atoms lying between the lay ers. K4M2+Mo4O15 (M2+ = Mg, Co, Cd) phases, which have similar structu res, have been synthesized and characterized.