Tight-binding modeling of interstitial ordering processes in metals: Application to zirconium hydrides

摘要: We present here a theoretical study of ordering processes in metal-hydrogen compounds based on generalized perturbation method and tight-binding coherent potential approximation. This approach is illustrated for zirconium hydrides, which case we demonstrate that cluster expansion the energy can be limited to effective pair interactions, leading one being between hydrogen atoms third-neighbor positions. These results are quantitatively confirmed by comparison density functional theory calculations qualitatively interpreted through orbital symmetry analysis. The then applied first draw preliminary Zr-H phase diagram characterize effect lattice deformation hydrides.