Ba(Si3N4)2 crystallizes in the orthorhombic Imm2 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent N(1), four equivalent N(2), and four equivalent N(3) 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 corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one N(1) and two equivalent N(2) atoms. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Si(1) atoms.
Ba(Si3N4)2 crystallizes in the orthorhombic Imm2 space group. Ba(1) is bonded in a 10-coordinate geometry to two equivalent N(1), four equivalent N(2), and four equivalent N(3) atoms. Both Ba(1)-N(1) bond lengths are 3.05 Å. All Ba(1)-N(2) bond lengths are 3.24 Å. There are two shorter (2.81 Å) and two longer (3.13 Å) Ba(1)-N(3) 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 corner-sharing SiN4 tetrahedra. The Si(1)-N(1) bond length is 1.77 Å. The Si(1)-N(3) bond length is 1.67 Å. Both Si(1)-N(2) bond lengths are 1.75 Å. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one N(1) and two equivalent N(2) atoms. The Si(2)-N(1) bond length is 1.74 Å. Both Si(2)-N(2) bond lengths are 1.75 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Ba(1), one Si(2), and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1) and two equivalent Si(1) atoms.