New molybdenum oxides Ag4M2Zr(MoO4)6 (M=Mg, Mn, Co, Zn) with a channel-like structure

New molybdenum oxides Ag4M2Zr(MoO4)6 (M=Mg, Mn, Co, Zn) have been synthesised by the solid state method. The structure of Ag4Mn2Zr(MoO4)6 has been studied by single-crystal X-ray and electron diffraction, high-resolution electron microscopy and second harmonic generation (SHG) technique. Ag4Mn2Zr(MoO4)6 crystallises in the orthorhombic space group P212121 with unit cell parameters: a=5.3632(1)Å, b=18.9463(3)Å, c=21.3621(4)Å. The 3D framework is formed by MnO6, ZrO6 octahedra and MoO4 tetrahedra connected via common vertices. The structure contents extensive channels along the [100] direction formed by four MnO6 octahedra and six MoO4 tetrahedra. Silver cations are located in these channels. The Ag4M2Zr(MoO4)6 (M=Mg, Co, Zn) compounds are isotypical with Ag4Mn2Zr(MoO4)6.