DOE OSTI2020
Ba3Ga3N5 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to six N3- atoms to form distorted BaN6 pentagonal pyramids that share corners with eight GaN4 tetrahedra and edges with four GaN4 tetrahedra. There are a spread of Ba–N bond distances ranging from 2.75–2.93 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight N3- atoms. There are a spread of Ba–N bond distances ranging from 2.92–3.15 Å. In the third Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Ba–N bond distances ranging from 2.71–3.29 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of Ba–N bond distances ranging from 2.75–3.08 Å. There are three inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four N3- atoms to form GaN4 tetrahedra that share a cornercorner with one BaN6 pentagonal pyramid, corners with two GaN4 tetrahedra, an edgeedge with one BaN6 pentagonal pyramid, and edges with two GaN4 tetrahedra. There are a spread of Ga–N bond distances ranging from 1.94–2.09 Å. In the second Ga3+ site, Ga3+ is bonded to four N3- atoms to form GaN4 tetrahedra that share corners with two equivalent BaN6 pentagonal pyramids, corners with two GaN4 tetrahedra, and edges with two GaN4 tetrahedra. There are a spread of Ga–N bond distances ranging from 1.94–2.08 Å. In the third Ga3+ site, Ga3+ is bonded to four N3- atoms to form distorted GaN4 tetrahedra that share a cornercorner with one BaN6 pentagonal pyramid, corners with two GaN4 tetrahedra, an edgeedge with one BaN6 pentagonal pyramid, and edges with two GaN4 tetrahedra. There are a spread of Ga–N bond distances ranging from 2.00–2.03 Å. There are five inequivalent N3- sites. In the first N3- site, N3- is bonded in a 2-coordinate geometry to four Ba2+ and two Ga3+ atoms. In the second N3- site, N3- is bonded in a 6-coordinate geometry to four Ba2+ and two Ga3+ atoms. In the third N3- site, N3- is bonded to three Ba2+ and three Ga3+ atoms to form a mixture of distorted corner and edge-sharing NBa3Ga3 octahedra. The corner-sharing octahedra tilt angles range from 24–83°. In the fourth N3- site, N3- is bonded to three Ba2+ and three Ga3+ atoms to form a mixture of distorted corner and edge-sharing NBa3Ga3 octahedra. The corner-sharing octahedra tilt angles range from 24–83°. In the fifth N3- site, N3- is bonded in a 6-coordinate geometry to four Ba2+ and two Ga3+ atoms.