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Structural studies and electrical properties of Cs/Al/Te/O phases with the pyrochlore structure
Jun Li1, Theeranun Siritanon, Judith K Stalick
1Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, USA.
Inorganic Chemistry
|May 11, 2011
Summary
This study details cesium aluminum tellurates with pyrochlore structures. Maximum electrical conductivity was observed near CsAl(1/3)Te(5/3)O(6), linked to Te 5s states influenced by lattice compression.
Area of Science:
- Materials Science
- Solid-State Chemistry
- Crystallography
Background:
- Cesium aluminum tellurates are investigated for their pyrochlore structure.
- Understanding structure-property relationships is crucial for advanced materials.
Purpose of the Study:
- To synthesize and characterize cesium aluminum tellurates with pyrochlore structures.
- To investigate the relationship between composition, structure, and electrical conductivity.
Main Methods:
- Polycrystalline and single crystal synthesis.
- X-ray and neutron diffraction for Rietveld structural analysis.
- Single crystal X-ray diffraction.
Main Results:
- Cell edge variations observed from 10.06 Å to 10.14 Å.
- Anharmonic thermal motion of Cs became significant upon substitution with Rb.
- Maximum electrical conductivity of ~0.1 S/cm found near CsAl(1/3)Te(5/3)O(6).
Conclusions:
- Electrical conductivity is attributed to Te 5s states influenced by lattice compression.
- Lattice compression increases conductivity by bringing filled Te 5s states closer to the conduction band.
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