BaSi6N8O crystallizes in the orthorhombic Imm2 space group. Ba(1) is bonded in a 6-coordinate geometry to two equivalent N(3) and four equivalent N(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form SiN4 tetrahedra that share corners with three equivalent Si(2)N3O tetrahedra and corners with four equivalent Si(1)N4 tetrahedra. In the second Si site, Si(2) is bonded to one N(3), two equivalent N(2), and one O(1) atom to form SiN3O tetrahedra that share  a cornercorner with one Si(2)N3O tetrahedra and corners with six equivalent Si(1)N4 tetrahedra. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(2) and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms.
BaSi6N8O crystallizes in the orthorhombic Imm2 space group. Ba(1) is bonded in a 6-coordinate geometry to two equivalent N(3) and four equivalent N(1) atoms. Both Ba(1)-N(3) bond lengths are 3.19 Å. There are two shorter (2.84 Å) and two longer (3.28 Å) Ba(1)-N(1) bond lengths. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form SiN4 tetrahedra that share corners with three equivalent Si(2)N3O tetrahedra and corners with four equivalent Si(1)N4 tetrahedra. The Si(1)-N(1) bond length is 1.69 Å. The Si(1)-N(3) bond length is 1.79 Å. There is one shorter (1.76 Å) and one longer (1.77 Å) Si(1)-N(2) bond length. In the second Si site, Si(2) is bonded to one N(3), two equivalent N(2), and one O(1) atom to form SiN3O tetrahedra that share  a cornercorner with one Si(2)N3O tetrahedra and corners with six equivalent Si(1)N4 tetrahedra. The Si(2)-N(3) bond length is 1.72 Å. Both Si(2)-N(2) bond lengths are 1.73 Å. The Si(2)-O(1) bond length is 1.63 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(2) and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a distorted trigonal planar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. O(1) is bonded in a bent 150 degrees geometry to two equivalent Si(2) atoms.