Materials Data on Ba3Si6N4O9 by Materials Project
Ba3Si6O9N4 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.74 Å) and three longer (2.76 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to one N3- and six O2- atoms. The Ba–N bond length is 3.21 Å. There are three shorter (2.74 Å) and three longer (2.87 Å) Ba–O bond lengths. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.73 Å) and three longer (2.85 Å) Ba–O bond lengths. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to two equivalent N3- and two O2- atoms to form corner-sharing SiN2O2 tetrahedra. There is one shorter (1.75 Å) and one longer (1.77 Å) Si–N bond length. There is one shorter (1.61 Å) and one longer (1.67 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to two N3- and two O2- atoms to form corner-sharing SiN2O2 tetrahedra. There is one shorter (1.75 Å) and one longer (1.76 Å) Si–N bond length. There is one shorter (1.62 Å) and one longer (1.67 Å) Si–O bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted trigonal planar geometry to one Ba2+ and three equivalent Si4+ atoms. In the second N3- site, N3- is bonded in a trigonal planar geometry to three Si4+ atoms. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one Si4+ atom.