LaSi3N5 crystallizes in the orthorhombic P2_12_12_1 space group. La(1) is bonded in a 9-coordinate geometry to one N(4), two equivalent N(1), two equivalent N(2), two equivalent N(3), and two equivalent N(5) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(2), one N(3), and one N(5) atom to form corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded to one N(2), one N(3), and two equivalent N(4) atoms to form corner-sharing SiN4 tetrahedra. In the third Si site, Si(3) is bonded to one N(1), one N(3), one N(4), and one N(5) atom to form corner-sharing SiN4 tetrahedra. There are five inequivalent N sites. In the first N site, N(5) is bonded to two equivalent La(1), one Si(1), and one Si(3) atom to form distorted corner-sharing NLa2Si2 tetrahedra. In the second N site, N(1) is bonded in a 2-coordinate geometry to two equivalent La(1), one Si(1), and one Si(3) atom. In the third N site, N(2) is bonded in a 2-coordinate geometry to two equivalent La(1), one Si(1), and one Si(2) atom. In the fourth N site, N(3) is bonded in a distorted trigonal planar geometry to two equivalent La(1), one Si(1), one Si(2), and one Si(3) atom. In the fifth N site, N(4) is bonded in a 3-coordinate geometry to one La(1), one Si(3), and two equivalent Si(2) atoms.
LaSi3N5 crystallizes in the orthorhombic P2_12_12_1 space group. La(1) is bonded in a 9-coordinate geometry to one N(4), two equivalent N(1), two equivalent N(2), two equivalent N(3), and two equivalent N(5) atoms. The La(1)-N(4) bond length is 2.87 Å. There is one shorter (2.57 Å) and one longer (2.89 Å) La(1)-N(1) bond length. There is one shorter (2.68 Å) and one longer (2.85 Å) La(1)-N(2) bond length. There is one shorter (3.12 Å) and one longer (3.13 Å) La(1)-N(3) bond length. There is one shorter (2.43 Å) and one longer (2.71 Å) La(1)-N(5) bond length. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(2), one N(3), and one N(5) atom to form corner-sharing SiN4 tetrahedra. The Si(1)-N(1) bond length is 1.69 Å. The Si(1)-N(2) bond length is 1.71 Å. The Si(1)-N(3) bond length is 1.80 Å. The Si(1)-N(5) bond length is 1.70 Å. In the second Si site, Si(2) is bonded to one N(2), one N(3), and two equivalent N(4) atoms to form corner-sharing SiN4 tetrahedra. The Si(2)-N(2) bond length is 1.69 Å. The Si(2)-N(3) bond length is 1.77 Å. There is one shorter (1.75 Å) and one longer (1.76 Å) Si(2)-N(4) bond length. In the third Si site, Si(3) is bonded to one N(1), one N(3), one N(4), and one N(5) atom to form corner-sharing SiN4 tetrahedra. The Si(3)-N(1) bond length is 1.68 Å. The Si(3)-N(3) bond length is 1.77 Å. The Si(3)-N(4) bond length is 1.77 Å. The Si(3)-N(5) bond length is 1.70 Å. There are five inequivalent N sites. In the first N site, N(5) is bonded to two equivalent La(1), one Si(1), and one Si(3) atom to form distorted corner-sharing NLa2Si2 tetrahedra. In the second N site, N(1) is bonded in a 2-coordinate geometry to two equivalent La(1), one Si(1), and one Si(3) atom. In the third N site, N(2) is bonded in a 2-coordinate geometry to two equivalent La(1), one Si(1), and one Si(2) atom. In the fourth N site, N(3) is bonded in a distorted trigonal planar geometry to two equivalent La(1), one Si(1), one Si(2), and one Si(3) atom. In the fifth N site, N(4) is bonded in a 3-coordinate geometry to one La(1), one Si(3), and two equivalent Si(2) atoms.