Structure and electronic properties of Mg-doped {beta}-rhombohedral boron constructed from icosahedral clusters
- Department of Advanced Materials Science, The University of Tokyo, 277-8561 Chiba (Japan)
- Department of Materials Science and Technology, Tokyo University of Science, 278-8510 Chiba (Japan)
- Institute for Multidisciplinary Research for Advanced Materials, Tohoku University, 980-8577 Miyagi (Japan)
High-T{sub C} superconductivity is possible upon metallic-element doping into {beta}-rhombohedral boron ({beta}-B{sub 105}), which is one of the boron icosahedral cluster solids. We attempted magnesium (Mg) doping into {beta}-B{sub 105} and discussed the possibility of metal transition and superconductivity. We achieved Mg doping into {beta}-B{sub 105} at a high Mg concentration of up to MgB{sub 11.5} (8.6 Mg/cell), i.e., electron doping sufficient for the Fermi energy (E{sub F}) to reach the conduction band over the intrinsic acceptor level (IAL) and trapping levels. However, neither metal transition nor superconductivity was observed. The changes in the structure and electronic properties are discussed on the basis of the results of x-ray powder diffraction using the Rietveld method and electrical conductivity and magnetic susceptibility measurements, respectively. We estimated the density of states near E{sub F} and discussed the electronic states of {beta}-B{sub 105}. From the result, it is suggested that a localized state exists above the IAL probably originating from the B{sub 28} cluster with structural defects.
- OSTI ID:
- 21070010
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 77, Issue 2; Other Information: DOI: 10.1103/PhysRevB.77.024515; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis, crystal growth and structure of Mg containing {beta}-rhombohedral boron: MgB{sub 17.4}
Superconductivity in Li-doped {alpha}-rhombohedral boron