Effect of mixed partial occupation of metal sites on the phase stability of γ-Cr_23-xFe _x C₆ (x = 0-3) carbides.

ABSTRACT: The effect of mixed partial occupation of metal sites on the phase stability of the γ-Cr_23-xFe _x C₆ (x = 0-3) carbides is explored as function of composition and temperature. Ab initio calculations combined with statistical thermodynamics approaches reveal that the site occupation of the carbides may be incorrectly predicted when only the commonly used approach of full sublattice occupation is considered. We found that the γ-M₂₃C₆ structure can be understood as a familiar sodium chloride structure with positively charged rhombic dodecahedron (M^(4a) M₁₂^(48h)) and negatively charged cubo-octahedron (M₈^(32f) C₆^(24e)) super-ion clusters, together with interstitial

SUBMITTER: Souissi M 

PROVIDER: S-EPMC5940797 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature