DOE OSTI2017
Mg14YCd crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are six inequivalent Mg sites. In the first Mg site, Mg is bonded to ten Mg and two equivalent Y atoms to form MgY2Mg10 cuboctahedra that share corners with four equivalent CdMg12 cuboctahedra, corners with fourteen MgY2Mg10 cuboctahedra, edges with two equivalent YMg12 cuboctahedra, edges with sixteen MgY2Mg10 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.12–3.34 Å. Both Mg–Y bond lengths are 3.23 Å. In the second Mg site, Mg is bonded to ten Mg and two equivalent Cd atoms to form distorted MgMg10Cd2 cuboctahedra that share corners with four equivalent YMg12 cuboctahedra, corners with fourteen MgY2Mg10 cuboctahedra, edges with two equivalent CdMg12 cuboctahedra, edges with sixteen MgMg10Cd2 cuboctahedra, faces with two equivalent CdMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.16–3.26 Å. Both Mg–Cd bond lengths are 3.23 Å. In the third Mg site, Mg is bonded to ten Mg and two equivalent Y atoms to form MgY2Mg10 cuboctahedra that share corners with four equivalent CdMg12 cuboctahedra, corners with fourteen MgMg10Cd2 cuboctahedra, edges with two equivalent YMg12 cuboctahedra, edges with sixteen MgY2Mg10 cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. There are two shorter (3.21 Å) and four longer (3.24 Å) Mg–Mg bond lengths. Both Mg–Y bond lengths are 3.23 Å. In the fourth Mg site, Mg is bonded to ten Mg, one Y, and one Cd atom to form distorted MgYMg10Cd cuboctahedra that share corners with eighteen MgYMg10Cd cuboctahedra, edges with two equivalent YMg12 cuboctahedra, edges with two equivalent CdMg12 cuboctahedra, edges with fourteen MgY2Mg10 cuboctahedra, a faceface with one YMg12 cuboctahedra, a faceface with one CdMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. There are four shorter (3.23 Å) and two longer (3.24 Å) Mg–Mg bond lengths. The Mg–Y bond length is 3.26 Å. The Mg–Cd bond length is 3.16 Å. In the fifth Mg site, Mg is bonded to ten Mg, one Y, and one Cd atom to form distorted MgYMg10Cd cuboctahedra that share corners with eighteen MgYMg10Cd cuboctahedra, edges with two equivalent YMg12 cuboctahedra, edges with two equivalent CdMg12 cuboctahedra, edges with fourteen MgY2Mg10 cuboctahedra, a faceface with one YMg12 cuboctahedra, a faceface with one CdMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. There are two shorter (3.23 Å) and two longer (3.24 Å) Mg–Mg bond lengths. The Mg–Y bond length is 3.26 Å. The Mg–Cd bond length is 3.16 Å. In the sixth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgYMg10Cd cuboctahedra, edges with eighteen MgY2Mg10 cuboctahedra, faces with three equivalent YMg12 cuboctahedra, faces with three equivalent CdMg12 cuboctahedra, and faces with fourteen MgY2Mg10 cuboctahedra. Y is bonded to twelve Mg atoms to form YMg12 cuboctahedra that share corners with six equivalent YMg12 cuboctahedra, corners with twelve equivalent MgMg10Cd2 cuboctahedra, edges with eighteen MgY2Mg10 cuboctahedra, faces with two equivalent CdMg12 cuboctahedra, and faces with eighteen MgY2Mg10 cuboctahedra. Cd is bonded to twelve Mg atoms to form CdMg12 cuboctahedra that share corners with six equivalent CdMg12 cuboctahedra, corners with twelve MgY2Mg10 cuboctahedra, edges with eighteen MgYMg10Cd cuboctahedra, faces with two equivalent YMg12 cuboctahedra, and faces with eighteen MgMg10Cd2 cuboctahedra.