The electronic states of p- and n-type Ba 8 Ga 16 Ge 30 (BGG) are studied by high-resolution x-ray photoelectron spectroscopy. In BGG, three bands are resolved in the valence band region. Theoretical calculations show that the three band structures in the valence band are mainly constructed by the Ge/Ga 4s and 4p wavefunctions with little contribution from Ba 5s, 5p, and 5d. The valence band around the Fermi level region of n-type BGG is sensitive to temperature, while that of p-BGG is stable when the temperature changes. The data indicate that the endohedral Ba in p- and n-type BGG rattle with different modes due to the different hybridization with the orbitals of the framework polyhedra.
- electronic structure
- x-ray photoelectron spectroscopy
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry