DOE OSTI2020
Ba6Yb6Al13Si11N29O13 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to two N3- and four O2- atoms to form distorted BaN2O4 octahedra that share a cornercorner with one BaN7 pentagonal bipyramid, corners with three SiN3O tetrahedra, and corners with nine AlN2O2 tetrahedra. There are one shorter (2.63 Å) and one longer (2.77 Å) Ba–N bond lengths. There are a spread of Ba–O bond distances ranging from 2.53–2.79 Å. In the second Ba2+ site, Ba2+ is bonded to two N3- and four O2- atoms to form BaN2O4 octahedra that share corners with five AlN3O tetrahedra, corners with five SiN4 tetrahedra, and corners with two equivalent AlN2O2 trigonal pyramids. There are one shorter (2.58 Å) and one longer (2.75 Å) Ba–N bond lengths. There are a spread of Ba–O bond distances ranging from 2.55–2.77 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to one N3- and five O2- atoms. The Ba–N bond length is 2.62 Å. There are a spread of Ba–O bond distances ranging from 2.60–2.99 Å. In the fourth Ba2+ site, Ba2+ is bonded to six N3- atoms to form distorted BaN6 octahedra that share corners with five SiN4 tetrahedra, corners with six AlN3O tetrahedra, a cornercorner with one AlN2O2 trigonal pyramid, and a faceface with one YbN4O2 pentagonal pyramid. There are a spread of Ba–N bond distances ranging from 2.61–2.73 Å. In the fifth Ba2+ site, Ba2+ is bonded to seven N3- atoms to form distorted BaN7 pentagonal bipyramids that share a cornercorner with one BaN2O4 octahedra, corners with three AlN3O tetrahedra, corners with seven SiN4 tetrahedra, and edges with two AlN3O tetrahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Ba–N bond distances ranging from 2.63–3.07 Å. In the sixth Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to six N3- and one O2- atom. There are a spread of Ba–N bond distances ranging from 2.63–2.70 Å. The Ba–O bond length is 3.13 Å. There are six inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Yb–N bond distances ranging from 2.32–2.71 Å. In the second Yb3+ site, Yb3+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of Yb–N bond distances ranging from 2.42–2.72 Å. In the third Yb3+ site, Yb3+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of Yb–N bond distances ranging from 2.34–2.70 Å. In the fourth Yb3+ site, Yb3+ is bonded in a 2-coordinate geometry to four N3- and four O2- atoms. There are a spread of Yb–N bond distances ranging from 2.36–3.02 Å. There are a spread of Yb–O bond distances ranging from 2.51–3.04 Å. In the fifth Yb3+ site, Yb3+ is bonded to four N3- and two O2- atoms to form distorted YbN4O2 pentagonal pyramids that share corners with two AlN3O tetrahedra, corners with four SiN4 tetrahedra, an edgeedge with one SiN4 tetrahedra, edges with two AlN3O tetrahedra, and a faceface with one BaN6 octahedra. There are a spread of Yb–N bond distances ranging from 2.44–2.53 Å. There are one shorter (2.49 Å) and one longer (2.51 Å) Yb–O bond lengths. In the sixth Yb3+ site, Yb3+ is bonded in a 6-coordinate geometry to four N3- and two O2- atoms. There are a spread of Yb–N bond distances ranging from 2.41–2.76 Å. There are one shorter (2.44 Å) and one longer (2.64 Å) Yb–O bond lengths. There are thirteen inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form distorted AlN3O tetrahedra that share a cornercorner with one BaN2O4 octahedra, corners with two equivalent BaN7 pentagonal bipyramids, and corners with six SiN4 tetrahedra. The corner-sharing octahedral tilt angles are 82°. There are a spread of Al–N bond distances ranging from 1.84–2.05 Å. The Al–O bond length is 1.85 Å. In the second Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with two equivalent BaN6 octahedra, a cornercorner with one YbN4O2 pentagonal pyramid, corners with two equivalent AlN3O tetrahedra, corners with four SiN4 tetrahedra, and an edgeedge with one YbN4O2 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 57–76°. There are a spread of Al–N bond distances ranging from 1.81–1.97 Å. The Al–O bond length is 1.97 Å. In the third Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form AlN2O2 tetrahedra that share corners with three equivalent BaN2O4 octahedra, corners with three AlN3O tetrahedra, and corners with three SiN3O tetrahedra. The corner-sharing octahedra tilt angles range from 68–75°. There is one shorter (1.80 Å) and one longer (1.85 Å) Al–N bond length. There is one shorter (1.81 Å) and one longer (1.83 Å) Al–O bond length. In the fourth Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with two equivalent BaN6 octahedra, a cornercorner with one YbN4O2 pentagonal pyramid, corners with two equivalent AlN3O tetrahedra, corners with four SiN4 tetrahedra, and an edgeedge with one YbN4O2 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 55–77°. There are a spread of Al–N bond distances ranging from 1.80–1.98 Å. The Al–O bond length is 1.95 Å. In the fifth Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with three BaN2O4 octahedra, corners with two equivalent AlN3O tetrahedra, corners with two SiN4 tetrahedra, and corners with two equivalent AlN2O2 trigonal pyramids. The corner-sharing octahedra tilt angles range from 54–91°. There are a spread of Al–N bond distances ranging from 1.84–1.97 Å. The Al–O bond length is 1.80 Å. In the sixth Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form AlN2O2 tetrahedra that share corners with two SiN4 tetrahedra and corners with four AlN2O2 tetrahedra. There is one shorter (1.87 Å) and one longer (1.99 Å) Al–N bond length. There is one shorter (1.78 Å) and one longer (1.79 Å) Al–O bond length. In the seventh Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with two equivalent BaN2O4 octahedra, a cornercorner with one SiN4 tetrahedra, corners with five AlN2O2 tetrahedra, and an edgeedge with one BaN7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 56–86°. There are a spread of Al–N bond distances ranging from 1.85–1.99 Å. The Al–O bond length is 1.82 Å. In the eighth Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form AlN2O2 tetrahedra that share corners with two SiN4 tetrahedra and corners with four AlN2O2 tetrahedra. There is one shorter (1.91 Å) and one longer (1.96 Å) Al–N bond length. There is one shorter (1.75 Å) and one longer (1.81 Å) Al–O bond length. In the ninth Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form distorted AlN3O tetrahedra that share corners with three BaN2O4 octahedra, corners with two equivalent AlN3O tetrahedra, corners with two SiN4 tetrahedra, and corners with two equivalent AlN2O2 trigonal pyramids. The corner-sharing octahedra tilt angles range from 55–89°. There are a spread of Al–N bond distances ranging from 1.83–2.03 Å. The Al–O bond length is 1.83 Å. In the tenth Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with two equivalent BaN2O4 octahedra, a cornercorner with one SiN4 tetrahedra, corners with five AlN2O2 tetrahedra, and an edgeedge with one BaN7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 60–76°. There are a spread of Al–N bond distances ranging from 1.85–2.01 Å. The Al–O bond length is 1.82 Å. In the eleventh Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form AlN2O2 tetrahedra that share corners with two SiN4 tetrahedra and corners with four AlN2O2 tetrahedra. There is one shorter (1.94 Å) and one longer (1.96 Å) Al–N bond length. There is one shorter (1.79 Å) and one longer (1.81 Å) Al–O bond length. In the twelfth Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form distorted AlN2O2 trigonal pyramids that share corners with three BaN2O4 octahedra, corners with two SiN4 tetrahedra, and corners with four AlN3O tetrahedra. The corner-sharing octahedra tilt angles range from 55–89°. There is one shorter (1.86 Å) and one longer (1.99 Å) Al–N bond length. Both Al–O bond lengths are 1.80 Å. In the thirteenth Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form distorted AlN2O2 tetrahedra that share corners with two equivalent BaN2O4 octahedra, a cornercorner with one BaN7 pentagonal bipyramid, a cornercorner with one SiN4 tetrahedra, and corners with five AlN2O2 tetrahedra. The corner-sharing octahedra tilt angles range from 70–74°. There is one shorter (1.86 Å) and one longer (1.99 Å) Al–N bond length. There is one shorter (1.81 Å) and one longer (1.85 Å) Al–O bond length. There are eleven inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to three N3- and one O2- atom to form distorted SiN3O tetrahedra that share a cornercorner with one BaN2O4 octahedra, a cornercorner with one AlN2O2 tetrahedra, and corners with five SiN3O tetrahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Si–N bond distances ranging from 1.71–1.98 Å. The Si–O bond length is 1.67 Å. In the second Si4+ site, Si4+ is bonded to four N3- atoms to form distorted SiN4 tetrahedra that share corners with three AlN2O2 tetrahedra and corners with three SiN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.66–1.77 Å. In the third Si4+ site, Si4+ is bonded to two N3- and two O2- atoms to form SiN2O2 tetrahedra that share corners with three equivalent YbN4O2 pentagonal pyramids, a cornercorner with one SiN4 tetrahedra, and corners with five AlN3O tetrahedra. There is one shorter (1.67 Å) and one longer (1.80 Å) Si–N bond length. There is one shorter (1.65 Å) and one longer (1.66 Å) Si–O bond length. In the fourth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with three equivalent BaN6 octahedra, a cornercorner with one SiN4 tetrahedra, corners with four AlN3O tetrahedra, and a cornercorner with one AlN2O2 trigonal pyramid. The corner-sharing octahedra tilt angles range from 66–76°. There is three shorter (1.72 Å) and one longer (1.82 Å) Si–N bond length. In the fifth Si4+ site, Si4+ is bonded to two N3- and two O2- atoms to form SiN2O2 tetrahedra that share corners with three equivalent BaN2O4 octahedra, corners with two SiN4 tetrahedra, corners with three AlN3O tetrahedra, and a cornercorner with one AlN2O2 trigonal pyramid. The corner-sharing octahedra tilt angles range from 63–73°. There is one shorter (1.67 Å) and one longer (1.72 Å) Si–N bond length. There is one shorter (1.66 Å) and one longer (1.72 Å) Si–O bond length. In the sixth Si4+ site, Si4+ is bonded to four N3- atoms to form distorted SiN4 tetrahedra that share corners with three equivalent BaN7 pentagonal bipyramids, corners with two SiN4 tetrahedra, and corners with four AlN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.67–1.78 Å. In the seventh Si4+ site, Si4+ is bonded to three N3- and one O2- atom to form distorted SiN3O tetrahedra that share a cornercorner with one BaN2O4 octahedra, corners with two equivalent BaN7 pentagonal bipyramids, corners with two equivalent AlN3O tetrahedra, and corners with four SiN4 tetrahedra. The corner-sharing octahedral tilt angles are 85°. There are a spread of Si–N bond distances ranging from 1.68–1.99 Å. The Si–O bond length is 1.73 Å. In the eighth Si4+ site, Si4+ is bonded to three N3- and one O2- atom to form SiN3O tetrahedra that share a cornercorner with one BaN2O4 octahedra, a cornercorner with one AlN2O2 tetrahedra, and corners with five SiN4 tetrahedra. The corner-sharing octahedral tilt angles are 71°. There are a spread of Si