DOI: 10.17188/1716963
title: Materials Data on Mg149Nb by Materials Project

description: Mg149Nb is alpha Samarium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. there are twenty-seven inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one NbMg12 cuboctahedra, corners with seventeen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.16–3.26 Å. In the second Mg site, Mg is bonded to eleven Mg and one Nb atom to form distorted MgMg11Nb cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one NbMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.09–3.23 Å. The Mg–Nb bond length is 3.10 Å. In the third Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are eight shorter (3.19 Å) and two longer (3.20 Å) Mg–Mg bond lengths. In the fourth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Nb cuboctahedra, an edgeedge with one NbMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are two shorter (3.17 Å) and four longer (3.18 Å) Mg–Mg bond lengths. In the fifth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg11Nb cuboctahedra, an edgeedge with one NbMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are four shorter (3.18 Å) and four longer (3.20 Å) Mg–Mg bond lengths. In the sixth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and six longer (3.19 Å) Mg–Mg bond lengths. In the seventh Mg site, Mg is bonded to eleven Mg and one Nb atom to form distorted MgMg11Nb cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one NbMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.11–3.23 Å. The Mg–Nb bond length is 3.09 Å. In the eighth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one NbMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. There are four shorter (3.18 Å) and three longer (3.19 Å) Mg–Mg bond lengths. In the ninth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the tenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, an edgeedge with one NbMg12 cuboctahedra, edges with seventeen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are two shorter (3.17 Å) and four longer (3.19 Å) Mg–Mg bond lengths. In the eleventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the twelfth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.20 Å. In the thirteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and three longer (3.19 Å) Mg–Mg bond lengths. In the fourteenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share a cornercorner with one NbMg12 cuboctahedra, corners with seventeen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.21 Å. In the fifteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.18–3.20 Å. In the sixteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the seventeenth Mg site, Mg is bonded to twelve Mg atoms to form MgMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, a faceface with one NbMg12 cuboctahedra, and faces with nineteen MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.18 Å. In the eighteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and one longer (3.19 Å) Mg–Mg bond lengths. In the nineteenth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are three shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the twentieth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and three longer (3.19 Å) Mg–Mg bond lengths. In the twenty-first Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are four shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the twenty-second Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are two shorter (3.18 Å) and two longer (3.19 Å) Mg–Mg bond lengths. In the twenty-third Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 3.17–3.19 Å. In the twenty-fourth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. All Mg–Mg bond lengths are 3.19 Å. In the twenty-fifth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. In the twenty-sixth Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.20 Å. In the twenty-seventh Mg site, Mg is bonded to twelve Mg atoms to form a mixture of face, edge, and corner-sharing MgMg12 cuboctahedra. Both Mg–Mg bond lengths are 3.20 Å. Nb is bonded to twelve Mg atoms to form NbMg12 cuboctahedra that share corners with eighteen MgMg12 cuboctahedra, edges with eighteen MgMg12 cuboctahedra, and faces with twenty MgMg11Nb cuboctahedra.