High-temperature order–disorder transitions in the skutterudites CoGe1.5Q1.5 (Q=S, Te)

Kaltzoglou, A., Powell, A., Knight, K. S. and Vaqueiro, P. ORCID: https://orcid.org/0000-0001-7545-6262 (2013) High-temperature order–disorder transitions in the skutterudites CoGe1.5Q1.5 (Q=S, Te). Journal of Solid State Chemistry, 198. pp. 525-531. ISSN 0022-4596 doi: 10.1016/j.jssc.2012.11.025

Abstract/Summary

The temperature dependence of anion ordering in the skutterudites CoGe1.5Q1.5 (Q=S, Te) has been investigated by powder neutron diffraction. Both materials adopt a rhombohedral structure at room temperature (space group R-3 ) in which the anions are ordered trans to each other within Ge2Q2 rings. In CoGe1.5S1.5, anion ordering is preserved up to the melting point of 950 °C. However, rhombohedral CoGe1.5Te1.5 undergoes a phase transition at 610 °C involving a change to cubic symmetry (space group Im-3). In the high-temperature modification, there is a statistical distribution of anions over the available sites within the Ge2Te2 rings. The structural transition involves a reduction in the degree of distortion of the Ge2Te2 rings which progressively transform from a rhombus to a rectangular shape. The effect of this transition on the thermoelectric properties has been investigated.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/39887
Item Type	Article
Refereed	Yes
Divisions	No Reading authors. Back catalogue items Life Sciences > School of Chemistry, Food and Pharmacy > Department of Chemistry Interdisciplinary centres and themes > Energy Research
Publisher	Elservier
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