La4O4BrCl3 is Matlockite-derived structured and crystallizes in the tetragonal P4mm space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 4-coordinate geometry to four equivalent O(1), one Br(1), and four equivalent Cl(2) atoms. In the second La site, La(2) is bonded in a 4-coordinate geometry to four equivalent O(2), one Cl(1), and four equivalent Cl(3) atoms. In the third La site, La(3) is bonded in a 4-coordinate geometry to four equivalent O(2), four equivalent Br(1), and one Cl(2) atom. In the fourth La site, La(4) is bonded in a 4-coordinate geometry to four equivalent O(1), one Cl(3), and four equivalent Cl(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent La(4) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the second O site, O(2) is bonded to two equivalent La(2) and two equivalent La(3) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. Br(1) is bonded in a 5-coordinate geometry to one La(1) and four equivalent La(3) atoms. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one La(2) and four equivalent La(4) atoms. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one La(3) and four equivalent La(1) atoms. In the third Cl site, Cl(3) is bonded in a 5-coordinate geometry to one La(4) and four equivalent La(2) atoms.
La4O4BrCl3 is Matlockite-derived structured and crystallizes in the tetragonal P4mm space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 4-coordinate geometry to four equivalent O(1), one Br(1), and four equivalent Cl(2) atoms. All La(1)-O(1) bond lengths are 2.39 Å. The La(1)-Br(1) bond length is 3.32 Å. All La(1)-Cl(2) bond lengths are 3.24 Å. In the second La site, La(2) is bonded in a 4-coordinate geometry to four equivalent O(2), one Cl(1), and four equivalent Cl(3) atoms. All La(2)-O(2) bond lengths are 2.40 Å. The La(2)-Cl(1) bond length is 3.29 Å. All La(2)-Cl(3) bond lengths are 3.23 Å. In the third La site, La(3) is bonded in a 4-coordinate geometry to four equivalent O(2), four equivalent Br(1), and one Cl(2) atom. All La(3)-O(2) bond lengths are 2.39 Å. All La(3)-Br(1) bond lengths are 3.28 Å. The La(3)-Cl(2) bond length is 3.41 Å. In the fourth La site, La(4) is bonded in a 4-coordinate geometry to four equivalent O(1), one Cl(3), and four equivalent Cl(1) atoms. All La(4)-O(1) bond lengths are 2.39 Å. The La(4)-Cl(3) bond length is 3.31 Å. All La(4)-Cl(1) bond lengths are 3.24 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent La(4) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. In the second O site, O(2) is bonded to two equivalent La(2) and two equivalent La(3) atoms to form a mixture of corner and edge-sharing OLa4 tetrahedra. Br(1) is bonded in a 5-coordinate geometry to one La(1) and four equivalent La(3) atoms. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a 5-coordinate geometry to one La(2) and four equivalent La(4) atoms. In the second Cl site, Cl(2) is bonded in a 5-coordinate geometry to one La(3) and four equivalent La(1) atoms. In the third Cl site, Cl(3) is bonded in a 5-coordinate geometry to one La(4) and four equivalent La(2) atoms.