First-principles prediction of stable phases in the Mg–Rh–B–H system

Chem. Met. Alloys 10 (2017) 99-105

https://doi.org/10.30970/cma10.0363

V.I. Ivaschenko, I.Yu. Zavaliy, P.E.A. Turchi, N.R. Medukh, Yu.V. Verbovytskyy

A first-principles investigation of plausible structures of the Mg–Rh–B–H system was carried out. The initial crystal structures of the Mg–Rh–B–H phases obtained by filling the voids in the Ti₂Ni structure type by boron or/and hydrogen atoms, were subsequently optimized. The optimum crystal structures were determined on the basis of an analysis of formation energies and densities of electronic states. The stable phases were predicted to be those in which the boron atoms form B@Rh₄ units, and the hydrogen atoms form H@RhMg₃ and H@Rh₄ units. Plausible origins of the stability of the Mg–Rh–B–H structures are discussed.

Reduced rhombohedral cell for Mg₁₆Rh₈H0₂H1₄H2₈H3₂.

Keywords

First-principles calculations / Crystal structure / Electronic state / Intermetallics / Hydride