DOE OSTI2020
Li8Nd7Ge10 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent Li sites. In the first Li site, Li is bonded to three Nd and four Ge atoms to form distorted LiNd3Ge4 tetrahedra that share corners with five equivalent LiNd3Ge4 tetrahedra, edges with two equivalent NdGe6 octahedra, edges with six LiNd3Ge4 tetrahedra, and faces with four LiNd3Ge4 tetrahedra. There are two shorter (3.14 Å) and one longer (3.19 Å) Li–Nd bond lengths. There are a spread of Li–Ge bond distances ranging from 2.64–2.77 Å. In the second Li site, Li is bonded to three Nd and four Ge atoms to form distorted LiNd3Ge4 tetrahedra that share a cornercorner with one NdGe6 octahedra, corners with four equivalent LiNd3Ge4 tetrahedra, edges with six LiNd3Ge4 tetrahedra, and faces with four LiNd3Ge4 tetrahedra. The corner-sharing octahedral tilt angles are 52°. There are two shorter (3.15 Å) and one longer (3.17 Å) Li–Nd bond lengths. There are a spread of Li–Ge bond distances ranging from 2.57–2.73 Å. There are four inequivalent Nd sites. In the first Nd site, Nd is bonded in a 6-coordinate geometry to six Li and six Ge atoms. There are four shorter (3.14 Å) and two longer (3.16 Å) Nd–Ge bond lengths. In the second Nd site, Nd is bonded in a 5-coordinate geometry to nine Ge atoms. There are a spread of Nd–Ge bond distances ranging from 3.13–3.33 Å. In the third Nd site, Nd is bonded in a 12-coordinate geometry to six Li and six Ge atoms. There are four shorter (3.20 Å) and two longer (3.21 Å) Nd–Ge bond lengths. In the fourth Nd site, Nd is bonded to six Ge atoms to form NdGe6 octahedra that share corners with four equivalent LiNd3Ge4 tetrahedra, edges with two equivalent NdGe6 octahedra, and edges with eight equivalent LiNd3Ge4 tetrahedra. There are four shorter (3.12 Å) and two longer (3.15 Å) Nd–Ge bond lengths. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 6-coordinate geometry to six Li and three Nd atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to six Li and three Nd atoms. In the third Ge site, Ge is bonded in a 2-coordinate geometry to two equivalent Li, six Nd, and one Ge atom. The Ge–Ge bond length is 2.55 Å. In the fourth Ge site, Ge is bonded in a 1-coordinate geometry to one Li, six Nd, and two equivalent Ge atoms. There are one shorter (2.51 Å) and one longer (2.53 Å) Ge–Ge bond lengths.