Materials Data on Sr4Li2Ta2Al2N8O by Materials Project
Li2Sr4Ta2Al2N8O crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Li1+ is bonded in a 2-coordinate geometry to two equivalent N3- and one O2- atom. There are one shorter (2.13 Å) and one longer (2.66 Å) Li–N bond lengths. The Li–O bond length is 1.86 Å. There are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to five N3- and one O2- atom. There are a spread of Sr–N bond distances ranging from 2.65–2.98 Å. The Sr–O bond length is 2.51 Å. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to seven N3- and one O2- atom. There are a spread of Sr–N bond distances ranging from 2.70–3.27 Å. The Sr–O bond length is 2.95 Å. Ta5+ is bonded to four N3- atoms to form TaN4 tetrahedra that share corners with four equivalent AlN4 tetrahedra. There are a spread of Ta–N bond distances ranging from 1.93–1.96 Å. Al3+ is bonded to four N3- atoms to form AlN4 tetrahedra that share corners with four equivalent TaN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.86–1.89 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a 2-coordinate geometry to three Sr2+, one Ta5+, and one Al3+ atom. In the second N3- site, N3- is bonded in a 5-coordinate geometry to three Sr2+, one Ta5+, and one Al3+ atom. In the third N3- site, N3- is bonded in a 2-coordinate geometry to four Sr2+, one Ta5+, and one Al3+ atom. In the fourth N3- site, N3- is bonded in a 3-coordinate geometry to two equivalent Li1+, two Sr2+, one Ta5+, and one Al3+ atom. O2- is bonded in a distorted octahedral geometry to two equivalent Li1+ and four Sr2+ atoms.