The new high-pressure borate hydrate Cu3B6O12 • H2O

The new compound Cu3B6O12 center dot H2O, synthesized under high-pressure/high-temperature conditions of 7.5 GPa and 700 degrees C in a Walker-type multianvil apparatus, possesses a structure similar to CuB2O4 (3 x CuB2O4 = Cu3B6O12). Via the high-pressure technique, it was possible to incorporate water molecules into the structure, leading to a symmetry reduction compared to the water free compound (I (4) over bar 2d -> Fdd2). Cu3B6O12 center dot H2O crystallizes in the orthorhombic space group Fdd2 (Z = 8) with the lattice parameters a = 1620.4(3), b = 1657.6(3), c = 564.2(2) pm, V = 1.5154(5) nm(3), R-1 = 0.0375, wR(2) = 0.0640 (all data). The crystal structure of Cu3B6O12 center dot H2O is built up from corner-sharing BO4 tetrahedra forming a three-dimensional network with channels along the c-axis. Inside these channels, the water molecules and a part of the copper ions are arranged. (C) 2011 Elsevier Masson SAS. All rights reserved.