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DOE OSTI · 1315548

Materials Data on MgRh5 by Materials Project

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Abstract

Rh5Mg crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Mg is bonded in a 12-coordinate geometry to ten Rh atoms. There are a spread of Mg–Rh bond distances ranging from 2.66–2.80 Å. There are five inequivalent Rh sites. In the first Rh site, Rh is bonded to two equivalent Mg and ten Rh atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with eight RhMg2Rh10 cuboctahedra, edges with nine RhMg2Rh5 cuboctahedra, and faces with six RhMg2Rh10 cuboctahedra. There are a spread of Rh–Rh bond distances ranging from 2.68–2.77 Å. In the second Rh site, Rh is bonded to two equivalent Mg and five Rh atoms to form distorted RhMg2Rh5 cuboctahedra that share corners with eleven RhMg2Rh10 cuboctahedra, edges with eight RhMg2Rh10 cuboctahedra, and faces with two equivalent RhMg2Rh5 cuboctahedra. Both Rh–Rh bond lengths are 2.77 Å. In the third Rh site, Rh is bonded in a distorted single-bond geometry to one Mg and five Rh atoms. There are one shorter (2.66 Å) and two longer (2.73 Å) Rh–Rh bond lengths. In the fourth Rh site, Rh is bonded to two equivalent Mg and ten Rh atoms to form distorted RhMg2Rh10 cuboctahedra that share corners with eleven RhMg2Rh5 cuboctahedra, edges with seven RhMg2Rh10 cuboctahedra, and faces with six RhMg2Rh10 cuboctahedra. There are two shorter (2.72 Å) and two longer (2.77 Å) Rh–Rh bond lengths. In the fifth Rh site, Rh is bonded in a 12-coordinate geometry to three equivalent Mg and four Rh atoms.

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36 MATERIALS SCIENCEcrystal structureMg-RhMgRh5

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2020-05-02. Materials Data on MgRh5 by Materials Project. https://doi.org/10.17188/1315548

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