Abstract:
We study the model of charge transfer in alloys proposed by Bruno, Zingales, and Wang (Phys. Rev. Lett. 91 (2003), 166401) and show its connection with electron-electron correlations. We investigate in detail the mechanism leading to the screening of the electrostatic interactions between atomic net charges in random alloys and calculate the screened interactions. We derive and discuss the probability distribution function of local charges. We also examine the validity of the frequently used approximations aimed at description of Coulomb effects within the CPA.