Electronic structure of random semiconductor alloys by the tight-binding linear muffin-tin orbital method

A new approach to the electronic structure of disorderd semiconductor alloys is developed, which combines the first-principles tight-binding linear muffin-tin orbital method with empty interstitial spheres to describe the electron states of open-structure materials, the coherent-potential approximation to treat the alloy disorder, and the Löwdin downfolding technique to take full advantage of the minimal basis set. Application is made to random ${\mathrm{Cd}}_{\mathrm{x}}$ ${\mathrm{Hg}}_{1\mathrm{-}\mathrm{x}}$Te alloys with a zinc-blende structure, but our approach is equally suitable for a description of semiconductor alloys with diamond, rocksalt, or fluorite structures.