La3SiN4F crystallizes in the orthorhombic Pnma space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to two equivalent N(2), two equivalent N(3), three equivalent N(1), and two equivalent F(1) atoms. In the second La site, La(2) is bonded in a 8-coordinate geometry to one N(2), one N(3), four equivalent N(1), and two equivalent F(1) atoms. Si(1) is bonded in a tetrahedral geometry to one N(2), one N(3), and two equivalent N(1) atoms. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 1-coordinate geometry to two equivalent La(2), three equivalent La(1), and one Si(1) atom. In the second N site, N(2) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Si(1) atom. In the third N site, N(3) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Si(1) atom. F(1) is bonded to two equivalent La(2) and four equivalent La(1) atoms to form distorted corner-sharing FLa6 octahedra. The corner-sharing octahedral tilt angles range from 38-47°.
La3SiN4F crystallizes in the orthorhombic Pnma space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to two equivalent N(2), two equivalent N(3), three equivalent N(1), and two equivalent F(1) atoms. There is one shorter (2.56 Å) and one longer (2.68 Å) La(1)-N(2) bond length. There is one shorter (2.64 Å) and one longer (2.87 Å) La(1)-N(3) bond length. There are a spread of La(1)-N(1) bond distances ranging from 2.67-3.01 Å. There is one shorter (2.74 Å) and one longer (2.77 Å) La(1)-F(1) bond length. In the second La site, La(2) is bonded in a 8-coordinate geometry to one N(2), one N(3), four equivalent N(1), and two equivalent F(1) atoms. The La(2)-N(2) bond length is 2.74 Å. The La(2)-N(3) bond length is 2.39 Å. There are two shorter (2.52 Å) and two longer (2.66 Å) La(2)-N(1) bond lengths. There is one shorter (2.63 Å) and one longer (2.95 Å) La(2)-F(1) bond length. Si(1) is bonded in a tetrahedral geometry to one N(2), one N(3), and two equivalent N(1) atoms. The Si(1)-N(2) bond length is 1.76 Å. The Si(1)-N(3) bond length is 1.75 Å. Both Si(1)-N(1) bond lengths are 1.73 Å. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 1-coordinate geometry to two equivalent La(2), three equivalent La(1), and one Si(1) atom. In the second N site, N(2) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Si(1) atom. In the third N site, N(3) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Si(1) atom. F(1) is bonded to two equivalent La(2) and four equivalent La(1) atoms to form distorted corner-sharing FLa6 octahedra. The corner-sharing octahedral tilt angles range from 38-47°.