Structural insights into the thermal decomposition sequence of barium tetrahydrogenorthotellurate(VI), Ba[H₄TeO₆]

Author(s)

Matthias Weil, Berthold Stöger, Christian Gierl-Mayer, Eugen Libowitzky

Abstract

The compounds Ba[H4TeO6] (I), Ba[H2TeO5] (II), Ba[Te2O6(OH)2] (III) and Ba[TeO4] (IV) were prepared by application of a diffusion method (I), under hydrothermal conditions (II and III) and from solid state reactions (IV), respectively. Structure analysis on the basis of single crystal X-ray diffraction data revealed novel structure types for (I), (II) and (III) and isotypism of (IV) with PrSbO4 and LaSbO4. Common feature of the four oxotellurate(VI) structures are [TeO6] octahedra. Whereas in the crystal structure of (I) the octahedral units are isolated, they are condensed into chains via corner-sharing in (II) and via edge-sharing in (III) and (IV). The coordination numbers of the barium cations in the four structures range from seven to ten. Although hydrogen atom positions could not be located for the structures of (I) and (II), short interpolyhedral O···O contacts are evident for strong hydrogen bonding. The temperature behaviour of (I), (II) and (IV) was monitored by simultaneous thermal analysis (STA) measurements and in situ powder X-ray diffraction, revealing the decomposition sequence Ba[H4TeO6] -> Ba[H2TeO5] -> Ba[TeO4] -> Ba[TeO3] upon heating to temperatures up to 900 °C.

Organisation(s)

Department of Mineralogy and Crystallography

External organisation(s)

Technische Universität Wien

Journal

Journal of Solid State Chemistry

Volume

241

Pages

187-197

No. of pages

11

ISSN

0022-4596

DOI

https://doi.org/10.1016/j.jssc.2016.06.010

Publication date

06-2016

Peer reviewed

Yes

Austrian Fields of Science 2012

104011 Materials chemistry, 105113 Crystallography

Keywords

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Ceramics and Composites, Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry

Portal url

https://ucrisportal.univie.ac.at/en/publications/887b31a3-0085-4efc-8950-64614fb7ba2b