Cooperative Jahn-Teller induced phase transition of TbVO<sub>4</sub>: single crystal structure analyses of the tetragonal high temperature phase and the twinned orthorhombic phase below 33 K
Kristin Kirschbaum; Anthony Martin; Damon A Parrish; A Alan Pinkerton; Kristin Kirschbaum; 2801 W Bancroft Street, Department of Chemistry, University of Toledo, Toledo, OH 43606, USA; Anthony Martin; 2801 W Bancroft Street, Department of Chemistry, University of Toledo, Toledo, OH 43606, USA; Damon A Parrish; 2801 W Bancroft Street, Department of Chemistry, University of Toledo, Toledo, OH 43606, USA; A Alan Pinkerton; 2801 W Bancroft Street, Department of Chemistry, University of Toledo, Toledo, OH 43606, USA
Журнал:
Journal of Physics: Condensed Matter
Дата:
1999-06-14
Аннотация:
The rare earth vanadate TbVO<sub>4</sub>, undergoes a crystallographic phase transition below 33 K induced by a cooperative Jahn-Teller effect. Twinning of the crystal occurs upon this transition from the tetragonal high temperature phase to the orthorhombic low temperature phase resulting in a domain structure. Single crystal x-ray analyses of the tetragonal and the twinned orthorhombic phase verify a reduction in the site symmetry of the Tb ion from D<sub>2d</sub> (m2-dodecahedral) for the high temperature phase to D<sub>2</sub> (222-distorted dodecahedral) for the low temperature phase. Concomitantly, the space group symmetry is lowered from D<sup>19</sup><sub>4h</sub> (I4<sub>1</sub>/amd) to D<sup>24</sup><sub>2h</sub> (Fddd). The twinned orthorhombic phase is described as domains related to each other by a 180° rotation about the orthorhombic [110] axis.
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