Na8[Zn4Ge8O18(OH)12]•2H2O:: An interrupted-framework zincogermanate built from [GeO3(OH)] and [Ge2(OH)2] units

A new layered germanate, Na-8[Zn4Ge8O18(OH)(12)]. 2H(2)O, has been synthesized from an aqueous solution containing germanium dioxide, zinc acetate and sodium hydroxide. Room temperature single crystal X-ray diffraction data indicate an orthorhombic cell with a = 13.036(3) Angstrom, b = 8.7286(17) Angstrom, c = 12.938(3) Angstrom, space group Pbcn (no. 60), and Z = 4. Chains of orthogonal four-rings, consisting of corner-sharing [Ge2Zn2] units bridged at the zinc centers, are connected to form a new tetrahedral sheet structure containing bifurcated 10-membered rings and the unique building blocks, [GeOn(OH)(4-n)] (n = 1, 2). The zincogermanate sheets are stacked along the c-axis and connected both by Na-O electrostatic interactions and a hydrogen bonding network composed of bound water molecules and terminal hydroxide anions.