ICT2014 Abstracts

Transition metal antimonide based thermoelectric materials exhibit interesting lattice dynamic properties, such as rattling in skutterudites, glass like interstitials and dumbbell rattling in zinc antimonide, as well a giant Seebeck coefficient attributed to phonon drag in iron diantimonide.

Inelastic scattering data obtained by inelastic x-ray scattering and nuclear inelastic scattering will be presented. The focus will be set on empty, FeSb3, and filled, EuFe4Sb12, skutterutides, as well as FeSb2. The lattice anharmonicity in these systems has been investigated through the use of temperature-dependent and high-pressure phonon spectroscopy. Via nuclear resonant inelastic scattering, element specific access to the density of phonon states for Moessbauer isotopes such as Eu, Fe, or Sb, is granted. Theoretical models for the lattice dynamics, most specifically for mode broadening through electron phonon coupling and for particular mode specific Grueneisen parameters will be discussed in the light of our latest experimental data.

Dres. Ilya Sergeev, Benedikt Klobes, Anne Houben, Matthieu Verstraete, David Johnson, and Mogens Christensen are acknowledged for the fruitful collaborations. The European Synchrotron Radiation Facility, DESY,  the Advanced Photon Source, and the Spallation Neutron Source are acknowledged for provision of beam time at ID22N/ID18, P01/P02, 6-ID-D, and POWGEN-III/ARCS, respectively. Funding from the DFG for priority program SPP1386 "Nanostrukturierte Thermoelektrika", and the Helmholtz Association of German Research Centers for projects NG-407 "Lattice dynamics in emerging functional materials" and HRJRG-402 "Sapphire ultraoptics for synchrotron radiation" is gratefully acknowledged.