BaLa4Ti4O15 crystallizes in the trigonal P-3c1 space group. Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ti(2)O6 octahedra, and faces with six equivalent Ti(1)O6 octahedra. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(3) atoms. In the second La site, La(2) is bonded in a 12-coordinate geometry to three equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra, and faces with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-19°. In the second Ti site, Ti(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 4-coordinate geometry to one La(2), two equivalent La(1), and one Ti(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one La(1), two equivalent La(2), one Ti(1), and one Ti(2) atom. In the third O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent La(2), and two equivalent Ti(1) atoms.
BaLa4Ti4O15 crystallizes in the trigonal P-3c1 space group. Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Ti(2)O6 octahedra, and faces with six equivalent Ti(1)O6 octahedra. All Ba(1)-O(1) bond lengths are 2.86 Å. There are three shorter (2.70 Å) and three longer (2.93 Å) Ba(1)-O(2) bond lengths. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(3) atoms. All La(1)-O(1) bond lengths are 2.88 Å. There are three shorter (2.45 Å) and three longer (2.62 Å) La(1)-O(3) bond lengths. In the second La site, La(2) is bonded in a 12-coordinate geometry to three equivalent O(2), three equivalent O(3), and six equivalent O(1) atoms. All La(2)-O(2) bond lengths are 2.91 Å. All La(2)-O(3) bond lengths are 2.57 Å. There are three shorter (2.49 Å) and three longer (3.15 Å) La(2)-O(1) bond lengths. There are two inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra, and faces with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 6-19°. All Ti(1)-O(1) bond lengths are 1.97 Å. All Ti(1)-O(2) bond lengths are 2.00 Å. In the second Ti site, Ti(2) is bonded to three equivalent O(1) and three equivalent O(3) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra and  a faceface with one Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. All Ti(2)-O(1) bond lengths are 2.13 Å. All Ti(2)-O(3) bond lengths are 1.88 Å. There are three inequivalent O sites. In the first O site, O(3) is bonded in a 4-coordinate geometry to one La(2), two equivalent La(1), and one Ti(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one La(1), two equivalent La(2), one Ti(1), and one Ti(2) atom. In the third O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent La(2), and two equivalent Ti(1) atoms.