Materials Data on Na3Sr3GaSb4 by Materials Project
Na3Sr3GaSb4 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Na1+ is bonded to four Sb3- atoms to form distorted NaSb4 tetrahedra that share corners with eight equivalent SrSb6 octahedra, corners with two equivalent GaSb4 tetrahedra, corners with eight equivalent NaSb4 tetrahedra, edges with two equivalent SrSb6 octahedra, an edgeedge with one GaSb4 tetrahedra, and faces with two equivalent SrSb6 octahedra. The corner-sharing octahedra tilt angles range from 27–55°. There are a spread of Na–Sb bond distances ranging from 3.13–3.39 Å. Sr2+ is bonded to six Sb3- atoms to form distorted SrSb6 octahedra that share corners with eight equivalent SrSb6 octahedra, a cornercorner with one GaSb4 tetrahedra, corners with eight equivalent NaSb4 tetrahedra, edges with four equivalent SrSb6 octahedra, an edgeedge with one GaSb4 tetrahedra, edges with two equivalent NaSb4 tetrahedra, faces with two equivalent SrSb6 octahedra, a faceface with one GaSb4 tetrahedra, and faces with two equivalent NaSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–50°. There are a spread of Sr–Sb bond distances ranging from 3.42–3.75 Å. Ga3+ is bonded to four Sb3- atoms to form GaSb4 tetrahedra that share corners with three equivalent SrSb6 octahedra, corners with six equivalent NaSb4 tetrahedra, edges with three equivalent SrSb6 octahedra, edges with three equivalent NaSb4 tetrahedra, and faces with three equivalent SrSb6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are three shorter (2.72 Å) and one longer (2.83 Å) Ga–Sb bond lengths. There are two inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded in a 10-coordinate geometry to three equivalent Na1+, six equivalent Sr2+, and one Ga3+ atom. In the second Sb3- site, Sb3- is bonded in a 8-coordinate geometry to three equivalent Na1+, four equivalent Sr2+, and one Ga3+ atom.