Materials Data on LiMg9B20 by Materials Project
LiMg9B20 is hexagonal omega structure-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li is bonded to twelve B atoms to form LiB12 cuboctahedra that share edges with twelve MgB12 cuboctahedra and faces with eight MgB12 cuboctahedra. There are a spread of Li–B bond distances ranging from 2.48–2.50 Å. There are five inequivalent Mg sites. In the first Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share edges with twelve MgB12 cuboctahedra, faces with two equivalent LiB12 cuboctahedra, and faces with six MgB12 cuboctahedra. There are a spread of Mg–B bond distances ranging from 2.48–2.50 Å. In the second Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share edges with three equivalent LiB12 cuboctahedra, edges with nine MgB12 cuboctahedra, and faces with eight MgB12 cuboctahedra. There are a spread of Mg–B bond distances ranging from 2.49–2.51 Å. In the third Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share an edgeedge with one LiB12 cuboctahedra, edges with eleven MgB12 cuboctahedra, a faceface with one LiB12 cuboctahedra, and faces with seven MgB12 cuboctahedra. There are a spread of Mg–B bond distances ranging from 2.48–2.51 Å. In the fourth Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share an edgeedge with one LiB12 cuboctahedra, edges with eleven MgB12 cuboctahedra, a faceface with one LiB12 cuboctahedra, and faces with seven MgB12 cuboctahedra. There are a spread of Mg–B bond distances ranging from 2.47–2.51 Å. In the fifth Mg site, Mg is bonded to twelve B atoms to form MgB12 cuboctahedra that share an edgeedge with one LiB12 cuboctahedra, edges with eleven MgB12 cuboctahedra, a faceface with one LiB12 cuboctahedra, and faces with seven MgB12 cuboctahedra. There are a spread of Mg–B bond distances ranging from 2.48–2.52 Å. There are ten inequivalent B sites. In the first B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. All B–B bond lengths are 1.77 Å. In the second B site, B is bonded in a 9-coordinate geometry to six Mg and three B atoms. Both B–B bond lengths are 1.78 Å. In the third B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. The B–B bond length is 1.76 Å. In the fourth B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. All B–B bond lengths are 1.77 Å. In the fifth B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. In the sixth B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. There is one shorter (1.75 Å) and one longer (1.79 Å) B–B bond length. In the seventh B site, B is bonded in a 9-coordinate geometry to six Mg and three B atoms. There is one shorter (1.76 Å) and one longer (1.77 Å) B–B bond length. In the eighth B site, B is bonded in a 9-coordinate geometry to one Li, five Mg, and three B atoms. The B–B bond length is 1.78 Å. In the ninth B site, B is bonded in a 9-coordinate geometry to six Mg and three B atoms. The B–B bond length is 1.79 Å. In the tenth B site, B is bonded in a 9-coordinate geometry to six Mg and three B atoms. The B–B bond length is 1.76 Å.