Na1.89Ag0.11[BP2O7(OH)] und Na2[BP2O7(OH)] – Isotype Borophosphate mit Tetraeder-Schichtpaketen

Na_1.89Ag_0.11[BP₂O₇(OH)] and Na₂[BP₂O₇(OH)] – Isotypic Borophosphates Containing Layered Tetrahedral Blocks The isotypic borophosphates Na_1.89Ag_0.11[BP₂O₇(OH)] and Na₂[BP₂O₇(OH)] were grown under mild hydrothermal conditions (T = 165–170 °C). The crystal structures were solved by single crystal methods in the case of Na_1.89Ag_0.11[BP₂O₇(OH)] and by refinement of powder data (Rietveld method) for Na₂[BP₂O₇(OH)], respectively (orthorhombic, Pna2₁ (No. 33); a = 683.98(14)/682.36(1) pm, b = 2086.5(4)/2079.11(4) pm, c = 1318.9(3)/1314.46(3) pm; Z = 12). The compounds contain a complex two-dimensional structure consisting of layered tetrahedral blocks, which are formed by six- and eight-membered rings of tetrahedra. The Na⁺/Ag⁺-ions are located inside and near the surface of the ‘layer blocks' and are five-, six- and sevenfold coordinated by oxygen.