• Huppertz, Hubert
• Teichtmeister, Tobias A.
• Hladik, Michael M.
• Heymann, Gunter

Abstract

<jats:title>Abstract</jats:title><jats:p>Using high-pressure/high-temperature synthesis methods, it was possible to increase the number of known borates with a crystal structure derived from gadolinite. Syntheses of Tb<jats:sub>2</jats:sub>Co(B<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub>)<jats:sub>2</jats:sub> (8 GPa, 1000 °C) and Tb<jats:sub>2</jats:sub>Cu(B<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub>)<jats:sub>2</jats:sub> (11 GPa, 650 °C) were carried out in a Walker-type multianvil device. The crystal structures were determined by single-crystal X-ray diffraction methods and Rietveld refinements of the powder patterns. The new compounds were further characterized by their infrared spectra. The lanthanoid cobalt and copper borates Tb<jats:sub>2</jats:sub>Co(B<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub>)<jats:sub>2</jats:sub> and Tb<jats:sub>2</jats:sub>Cu(B<jats:sub>2</jats:sub>O<jats:sub>5</jats:sub>)<jats:sub>2</jats:sub> crystallize in the monoclinic space group <jats:italic>P</jats:italic>2<jats:sub>1</jats:sub>/<jats:italic>c</jats:italic> (no. 14) with the unit cell parameters <jats:italic>a</jats:italic> = 4.5630(1), <jats:italic>b</jats:italic> = 7.2991(2), <jats:italic>c</jats:italic> = 9.4161(2) Å, and <jats:italic>β</jats:italic> = 91.14(1)° for the cobalt and <jats:italic>a</jats:italic> = 4.5757(1), <jats:italic>b</jats:italic> = 7.3078(2), <jats:italic>c</jats:italic> = 9.3771(3) Å, <jats:italic>β</jats:italic> = 90.73(1)° for the copper compound.</jats:p>

Topics

• compound
• x-ray diffraction
• copper
• cobalt
• space group
• diffraction method