We report a systematic study of the rhenium-based borides, ReB2, Re7 B3, and Re3 B, by means of the B 11 nuclear magnetic resonance (NMR) spectroscopy. While Re7 B3 and Re3 B are superconductors, ReB2 exhibits no superconducting signature but is of current interest due to its superhard mechanical property. Since the major focus of this investigation is their electronic characteristics in the normal states, we performed the measurements at temperatures between 77 and 295 K. For Re7 B3 and Re3 B, s -character electrons were found to be responsible for the observed B 11 NMR Knight shift and spin-lattice relaxation rate (1/ T1). From T1 analysis, we thus deduce the partial Bs Fermi-level density of states (DOS) of both borides. On the other hand, the relaxation rate of ReB2 is mainly associated with p electrons, similar to the cases of OsB2 and RuB2. In addition, the extracted B2p Fermi-level DOS is in good agreement with the theoretical prediction from band-structure calculations.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2008 Jul 11|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics