DOE OSTI2020
La10Br4Ga5 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are three inequivalent La sites. In the first La site, La is bonded to five Ga atoms to form a mixture of distorted edge and corner-sharing LaGa5 trigonal bipyramids. There are a spread of La–Ga bond distances ranging from 3.28–3.41 Å. In the second La site, La is bonded in a 8-coordinate geometry to three equivalent Ga and five Br atoms. There are one shorter (3.13 Å) and two longer (3.17 Å) La–Ga bond lengths. There are a spread of La–Br bond distances ranging from 3.10–3.52 Å. In the third La site, La is bonded in a 6-coordinate geometry to five Ga and one Br atom. There are one shorter (3.13 Å) and four longer (3.31 Å) La–Ga bond lengths. The La–Br bond length is 3.19 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded in a 9-coordinate geometry to eight La and one Ga atom. The Ga–Ga bond length is 2.84 Å. In the second Ga site, Ga is bonded in a distorted q6 geometry to ten La atoms. There are two inequivalent Br sites. In the first Br site, Br is bonded to five La atoms to form corner-sharing BrLa5 square pyramids. In the second Br site, Br is bonded in a 6-coordinate geometry to six equivalent La atoms.