Ba2La3Ti3NbO15 crystallizes in the trigonal P3c1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to three equivalent O(1), three equivalent O(3), and six equivalent O(4) atoms. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent O(2), three equivalent O(4), and six equivalent O(3) atoms. There are three inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(4) atoms. In the second La site, La(2) is bonded in a 9-coordinate geometry to three equivalent O(2), three equivalent O(3), and three equivalent O(5) atoms. In the third La site, La(3) is bonded in a 9-coordinate geometry to three equivalent O(1), three equivalent O(2), and three equivalent O(5) atoms. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 19-21°. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-20°. In the third Ti site, Ti(3) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 21°. Nb(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with three equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are five inequivalent O sites. In the first O site, O(4) is bonded in a 1-coordinate geometry to one Ba(2), two equivalent Ba(1), one La(1), and one Ti(3) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one La(2), one La(3), one Ti(1), and one Ti(2) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), one La(1), one La(3), one Ti(1), and one Ti(3) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Ba(2), one La(2), one La(3), one Ti(2), and one Nb(1) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), one La(2), and one Nb(1) atom.
Ba2La3Ti3NbO15 crystallizes in the trigonal P3c1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to three equivalent O(1), three equivalent O(3), and six equivalent O(4) atoms. All Ba(1)-O(1) bond lengths are 3.28 Å. All Ba(1)-O(3) bond lengths are 2.84 Å. There are three shorter (2.73 Å) and three longer (3.04 Å) Ba(1)-O(4) bond lengths. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to three equivalent O(2), three equivalent O(4), and six equivalent O(3) atoms. All Ba(2)-O(2) bond lengths are 3.37 Å. All Ba(2)-O(4) bond lengths are 2.79 Å. There are three shorter (2.73 Å) and three longer (3.08 Å) Ba(2)-O(3) bond lengths. There are three inequivalent La sites. In the first La site, La(1) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(4) atoms. All La(1)-O(1) bond lengths are 2.58 Å. All La(1)-O(4) bond lengths are 2.43 Å. In the second La site, La(2) is bonded in a 9-coordinate geometry to three equivalent O(2), three equivalent O(3), and three equivalent O(5) atoms. All La(2)-O(2) bond lengths are 2.52 Å. All La(2)-O(3) bond lengths are 2.56 Å. All La(2)-O(5) bond lengths are 2.91 Å. In the third La site, La(3) is bonded in a 9-coordinate geometry to three equivalent O(1), three equivalent O(2), and three equivalent O(5) atoms. All La(3)-O(1) bond lengths are 2.66 Å. All La(3)-O(2) bond lengths are 2.74 Å. All La(3)-O(5) bond lengths are 2.50 Å. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles range from 19-21°. All Ti(1)-O(1) bond lengths are 1.91 Å. All Ti(1)-O(5) bond lengths are 2.08 Å. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra and corners with three equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 19-20°. All Ti(2)-O(2) bond lengths are 1.99 Å. All Ti(2)-O(5) bond lengths are 1.98 Å. In the third Ti site, Ti(3) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form distorted corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 21°. All Ti(3)-O(1) bond lengths are 2.21 Å. All Ti(3)-O(4) bond lengths are 1.83 Å. Nb(1) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with three equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles are 20°. All Nb(1)-O(2) bond lengths are 2.18 Å. All Nb(1)-O(3) bond lengths are 1.89 Å. There are five inequivalent O sites. In the first O site, O(4) is bonded in a 1-coordinate geometry to one Ba(2), two equivalent Ba(1), one La(1), and one Ti(3) atom. In the second O site, O(5) is bonded in a 3-coordinate geometry to one La(2), one La(3), one Ti(1), and one Ti(2) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Ba(1), one La(1), one La(3), one Ti(1), and one Ti(3) atom. In the fourth O site, O(2) is bonded in a 4-coordinate geometry to one Ba(2), one La(2), one La(3), one Ti(2), and one Nb(1) atom. In the fifth O site, O(3) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), one La(2), and one Nb(1) atom.