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Z. Naturforsch. 2012,
67b, 1197 – 1204
doi:10.5560/ZNB.2012-0248
High-pressure Synthesis and Characterization of the Alkali Metal Borate HP-RbB3O5
1 Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80–82, A-6020 Innsbruck, Austria
2 Tyrolit Schleifmittelwerke Swarovski K.G., Swarovskistraße 33, A-6130 Schwaz, Austria
Reprint requests to H. Huppertz. E-mail:
Hubert.Huppertz@uibk.ac.at
Received August 4, 2012 / published online November 12, 2012
The rubidium triborate HP-RbB3O5 (HP = high-pressure) was synthesized under high-pressure/high-temperature conditions of 6 GPa and 1000 °C in a Walker-type multianvil apparatus. The precursor was gained from a mixture of rubidium carbonate Rb2CO3 and boric acid H3BO3 heated at 850 °C under normal pressure conditions. The single-crystal structure determination showed that HP-RbB3O5 is isotypic to HP-KB3O5, crystallizing monoclinically with eight formula units in the space group C2/c possessing the lattice parameters a = 982.3(2), b = 885.9(2), c = 919.9(2) pm, and β =104.0(1)°. The boron-oxygen framework consists of trigonal-planar BO3 groups as well as corner- and edge-sharing BO4 tetrahedra that are connected to a three-dimensional framework. Therein, the rubidium cations are surrounded by 10 oxygen anions. IR- and Raman-spectroscopic investigations were performed on single crystals of the compound.
Key words: High Pressure, Borate, Crystal Structure