Structure and physical properties of type-I clathrate solid-solution Ba8 Ptx Ge46-x-y y (=vacancy)
- Autor(en)
- Nataliya Melnychenko-Koblyuk, Andrij Grytsiv, Peter Franz Rogl, Martin Rotter, Roman Lackner, Ernst Bauer, L Fornasari, F Marabelli, Gerald Giester
- Abstrakt
Formation, crystal chemistry, and physical properties were investigated for the solid-solution Ba8 Ptx Ge46-x-y y (is a vacancy) deriving from binary clathrate Ba8 Ge43 3 with a solubility limit of ?3.5 Pt atoms/f.u. at T=800°C. Structural investigations throughout the homogeneity region confirm isotypism with the cubic primitive clathrate type-I structure (space group type Pm 3? n) and lattice parameters ranging from a=1.0657 (2) nm for Ba8 Ge43 3 to a=1.0752 (2) nm for Ba8 Pt3.5 Ge41.5 1.0. Phase relations for the region concerning the clathrate solution were derived at subsolidus temperatures as well as at 800°C. Transport properties evidence electrons as the majority charge carriers in the system with a slight dependency on the Pt content. The system is located close to a semiconducting regime with a gap in the electronic density of states of a few thousand K. No low temperature maximum is obvious from thermal conductivity which is dominated by the lattice contribution. Thermal conductivity furthermore documents a high efficiency of phonon scattering on vacancies. © 2007 The American Physical Society.
- Organisation(en)
- Institut für Physikalische Chemie, Institut für Mineralogie und Kristallographie
- Externe Organisation(en)
- Technische Universität Wien, Università degli studi di Pavia
- Journal
- Physical Review B
- Band
- 76
- Seiten
- 1951241-1951247
- Anzahl der Seiten
- 7
- ISSN
- 1098-0121
- Publikationsdatum
- 2007
- Peer-reviewed
- Ja
- ÖFOS 2012
- 104017 Physikalische Chemie, 105113 Kristallographie
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/2e0953ee-4078-4615-b41e-65a25875be93