Materials Data on CeMg6Cr by Materials Project

Abstract

Mg6CeCr crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to eight Mg, two equivalent Ce, and two equivalent Cr atoms to form MgCe2Mg8Cr2 cuboctahedra that share corners with four equivalent CeMg10Cr2 cuboctahedra, corners with four equivalent CrCe2Mg10 cuboctahedra, corners with ten equivalent MgCe2Mg8Cr2 cuboctahedra, edges with two equivalent CeMg10Cr2 cuboctahedra, edges with two equivalent CrCe2Mg10 cuboctahedra, edges with fourteen MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CeMg10Cr2 cuboctahedra, faces with two equivalent CrCe2Mg10 cuboctahedra, and faces with sixteen MgCe2Mg8Cr2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.07–3.22 Å. There are one shorter (3.30 Å) and one longer (3.31 Å) Mg–Ce bond lengths. There are one shorter (3.24 Å) and one longer (3.37 Å) Mg–Cr bond lengths. In the second Mg site, Mg is bonded to eight Mg, two equivalent Ce, and two equivalent Cr atoms to form distorted MgCe2Mg8Cr2 cuboctahedra that share corners with eighteen MgCe2Mg8Cr2 cuboctahedra, edges with four equivalent CeMg10Cr2 cuboctahedra, edges with four equivalent CrCe2Mg10 cuboctahedra, edges with ten MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CeMg10Cr2 cuboctahedra, faces with two equivalent CrCe2Mg10 cuboctahedra, and faces with sixteen MgCe2Mg8Cr2 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.99–3.41 Å. Both Mg–Ce bond lengths are 3.22 Å. Both Mg–Cr bond lengths are 3.13 Å. In the third Mg site, Mg is bonded to ten Mg and two equivalent Ce atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with eighteen MgCe2Mg8Cr2 cuboctahedra, edges with four equivalent CeMg10Cr2 cuboctahedra, edges with fourteen MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CeMg10Cr2 cuboctahedra, faces with six equivalent CrCe2Mg10 cuboctahedra, and faces with twelve MgCe2Mg8Cr2 cuboctahedra. Both Mg–Mg bond lengths are 3.14 Å. Both Mg–Ce bond lengths are 3.25 Å. In the fourth Mg site, Mg is bonded to ten Mg and two equivalent Cr atoms to form distorted MgMg10Cr2 cuboctahedra that share corners with eighteen MgCe2Mg8Cr2 cuboctahedra, edges with four equivalent CrCe2Mg10 cuboctahedra, edges with fourteen MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CrCe2Mg10 cuboctahedra, faces with six equivalent CeMg10Cr2 cuboctahedra, and faces with twelve MgCe2Mg8Cr2 cuboctahedra. Both Mg–Cr bond lengths are 3.21 Å. Ce is bonded to ten Mg and two equivalent Cr atoms to form CeMg10Cr2 cuboctahedra that share corners with four equivalent CrCe2Mg10 cuboctahedra, corners with six equivalent CeMg10Cr2 cuboctahedra, corners with eight equivalent MgCe2Mg8Cr2 cuboctahedra, edges with two equivalent CrCe2Mg10 cuboctahedra, edges with sixteen MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CeMg10Cr2 cuboctahedra, faces with two equivalent CrCe2Mg10 cuboctahedra, and faces with sixteen MgCe2Mg8Cr2 cuboctahedra. Both Ce–Cr bond lengths are 3.14 Å. Cr is bonded to ten Mg and two equivalent Ce atoms to form CrCe2Mg10 cuboctahedra that share corners with four equivalent CeMg10Cr2 cuboctahedra, corners with six equivalent CrCe2Mg10 cuboctahedra, corners with eight equivalent MgCe2Mg8Cr2 cuboctahedra, edges with two equivalent CeMg10Cr2 cuboctahedra, edges with sixteen MgCe2Mg8Cr2 cuboctahedra, faces with two equivalent CeMg10Cr2 cuboctahedra, faces with two equivalent CrCe2Mg10 cuboctahedra, and faces with sixteen MgCe2Mg8Cr2 cuboctahedra.