Abstract
The electronic structures of the hexagonal and phases are calculated from first-principles using the TB-LMTO method. These ab initio results are analyzed with a simplified model for Al-based alloys containing transition metal atoms. The results show a strong effect on the atomic structure stabilization by an effective Mn-Mn interaction mediated by conduction electrons over medium-range distances (5 Å and more). The origin of large vacancies which characterize such atomic structures is explained. The position and the effect of Si atoms in stabilizing are also discussed. The atomic structures of and bear resemblance with the atomic medium-range structures of approximants of quasicrystals. Consequently, the present work gives arguments on the interplay between the medium-range atomic order and an minimization of the band energy in quasicrystals and related phases.
- Received 24 December 2002
DOI:https://doi.org/10.1103/PhysRevB.68.045117
©2003 American Physical Society