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Structural and Physical Properties of Rare-Earth Clathrates

  • Silke PaschenEmail author
  • Matthias IkedaEmail author
  • Stevce StefanoskiEmail author
  • George S. NolasEmail author
Chapter
Part of the Springer Series in Materials Science book series (SSMATERIALS, volume 199)

Abstract

Clathrates that contain rare-earth elements as guest atoms have been of active interest since the discovery of intermetallic clathrates. A large body of work focussed on thermoelectric properties of Eu-containing clathrates. The very low lattice thermal conductivities that are reached in Eu-containing type-I clathrates are generally attributed to the pronounced rattling of Eu in oversized host cages and to the occurrence of split sites in the larger of the two cages of the structure. The potential of Eu-containing clathrates for magnetic refrigeration has been recognized more recently. Here, key features are the large magnetic moment of Eu, together with the second order character of the paramagnetic to ferromagnetic phase transition. The incorporation of other magnetic rare-earth elements into the clathrate cages has long remained elusive. Only very recently the successful synthesis of a cerium containing type-I clathrate was reported. Interestingly, a sizable enhancement of the thermopower is observed and attributed to a rattling enhanced Kondo interaction. This discovery may trigger a wealth of future investigations.

Keywords

Thermoelectric Property Lattice Thermal Conductivity Charge Carrier Concentration Magnetic Entropy Change Magnetic Refrigeration 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

SP and MI acknowledge support by the Priority Program “Nanostructured Thermoelectric Materials: Theory, Model Systems and Controlled Synthesis” (SPP 1386) of the Deutsche Forschungsgemeinschaft and from the Austrian Science Fund (projects TRP 176-N22 and I623-N16). SS and GSN acknowledge support from the Army Research Office under Grant No. W911NF-08-1-0276 for research on Eu-clathrates for magnetocaloric applications.

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© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Institute of Solid State PhysicsVienna University of TechnologyViennaAustria
  2. 2.Geophysical LaboratoryCarnegie Institution of WashingtonWashingtonUSA
  3. 3.Department of PhysicsUniversity of South FloridaTampaUSA

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