DOI: 10.17188/1316148
title: Materials Data on Sm5Mg by Materials Project

description: MgSm5 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Mg is bonded to twelve Sm atoms to form MgSm12 cuboctahedra that share corners with six equivalent MgSm12 cuboctahedra, corners with twelve equivalent SmSm9Mg3 cuboctahedra, edges with six equivalent MgSm12 cuboctahedra, edges with twelve SmSm10Mg2 cuboctahedra, and faces with twenty SmSm10Mg2 cuboctahedra. There are six shorter (3.51 Å) and six longer (3.61 Å) Mg–Sm bond lengths. There are six inequivalent Sm sites. In the first Sm site, Sm is bonded to two equivalent Mg and ten Sm atoms to form distorted SmSm10Mg2 cuboctahedra that share corners with eighteen SmSm10Mg2 cuboctahedra, edges with four equivalent MgSm12 cuboctahedra, edges with fourteen SmSm10Mg2 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. There are a spread of Sm–Sm bond distances ranging from 3.51–3.75 Å. In the second Sm site, Sm is bonded to two equivalent Mg and ten Sm atoms to form distorted SmSm10Mg2 cuboctahedra that share corners with eighteen SmSm10Mg2 cuboctahedra, edges with four equivalent MgSm12 cuboctahedra, edges with fourteen SmSm10Mg2 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. There are a spread of Sm–Sm bond distances ranging from 3.51–3.75 Å. In the third Sm site, Sm is bonded to two equivalent Mg and ten Sm atoms to form distorted SmSm10Mg2 cuboctahedra that share corners with eighteen SmSm10Mg2 cuboctahedra, edges with four equivalent MgSm12 cuboctahedra, edges with fourteen SmSm10Mg2 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. There are a spread of Sm–Sm bond distances ranging from 3.51–3.75 Å. In the fourth Sm site, Sm is bonded to three equivalent Mg and nine Sm atoms to form SmSm9Mg3 cuboctahedra that share corners with six equivalent MgSm12 cuboctahedra, corners with twelve equivalent SmSm9Mg3 cuboctahedra, edges with eighteen SmSm10Mg2 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. There are one shorter (3.57 Å) and three longer (3.61 Å) Sm–Sm bond lengths. In the fifth Sm site, Sm is bonded to two equivalent Mg and ten Sm atoms to form distorted SmSm10Mg2 cuboctahedra that share corners with eighteen SmSm10Mg2 cuboctahedra, edges with four equivalent MgSm12 cuboctahedra, edges with fourteen SmSm9Mg3 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. There are two shorter (3.55 Å) and one longer (3.75 Å) Sm–Sm bond lengths. In the sixth Sm site, Sm is bonded to two equivalent Mg and ten Sm atoms to form distorted SmSm10Mg2 cuboctahedra that share corners with eighteen SmSm10Mg2 cuboctahedra, edges with four equivalent MgSm12 cuboctahedra, edges with fourteen SmSm10Mg2 cuboctahedra, faces with four equivalent MgSm12 cuboctahedra, and faces with sixteen SmSm10Mg2 cuboctahedra. Both Sm–Mg bond lengths are 3.51 Å. There are a spread of Sm–Sm bond distances ranging from 3.51–3.75 Å.