Abstract
We present ab initio calculations of magnetic moments and local electronic densities of states in binary and ternary Si random alloys with -derived structures. The local-spin-density approximation, the linear muffin-tin orbital method, and the coherent-potential approximation (LMTO-CPA) were used. In the excess (as compared to Si) Fe atoms occupy the Si[D] sites of the Si host and create a strong d scattering. A realistic-alloy calculation thus requires the application of the CPA. In both types of alloys the moments of Fe atoms occupying the B sites remain essentially unchanged when the concentrations (y in , x in Si) are varied. The Fe[A,C] moments vary almost linearly with y and x, in agreement with experimental observations. The sublattice density-of-states functions provide insight into the site preference for substitutional transition-metal impurities in Si.
- Received 17 August 1990
DOI:https://doi.org/10.1103/PhysRevB.43.5924
©1991 American Physical Society