Silicon and germanium network polyhedra viewed from soft X-ray spectroscopy

Jun Tang, Takeshi Rachi, Marcos A. Avila, Toshiro Takabatake, Fag Zhum Guo, Keisuke Kobayashi, Koji Akai, Katsumi Tanigaki

Research output: Contribution to journalConference articlepeer-review


The electronic states of Ba8Ga16Ge30 and Sr8Ga16Ge30 are studied by soft x-ray photoelectron spectroscopy (XPS) at a high-energy facility. In Ba 8Ga16Ge30, three bands are resolved in the valence band region. Resonance experiments together with theoretical calculations show that the three band structures in the valence band are mainly constructed by the Ge/Ga 4s and 4p wave functions with little contributions of Ba 5s, 5p and 5d. The valence band of Sr8Ga16Ge 30 shows a similar feature to that of Ba8Ga 16Ge30. It is clearly shown that the atomic orbitals of Ba and Sr make little hybridization with the orbitals made by the framework polyhedra. This provides the understanding of the thermoelectricity in clathrates, and assists the design in high performance thermoelectric materials in this family.

Original languageEnglish
Pages (from-to)167-171
Number of pages5
JournalMaterials Research Society Symposium Proceedings
Publication statusPublished - 2008
Externally publishedYes
EventThermoelectric Power Generation - Boston, MA, United States
Duration: 2007 Nov 262007 Nov 29

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'Silicon and germanium network polyhedra viewed from soft X-ray spectroscopy'. Together they form a unique fingerprint.

Cite this