Fe3B7O13Br crystallizes in the trigonal R3c space group. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one Br(1) atom to form distorted FeBrO4 trigonal bipyramids that share corners with three equivalent B(2)O4 tetrahedra, corners with four equivalent B(3)O4 tetrahedra, and corners with two equivalent Fe(1)BrO4 trigonal bipyramids. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. In the second B site, B(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form BO4 tetrahedra that share corners with two equivalent B(2)O4 tetrahedra, corners with three equivalent B(3)O4 tetrahedra, and corners with three equivalent Fe(1)BrO4 trigonal bipyramids. In the third B site, B(3) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form BO4 tetrahedra that share corners with three equivalent B(2)O4 tetrahedra and corners with four equivalent Fe(1)BrO4 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(1), and one B(3) atom. In the second O site, O(5) is bonded in a trigonal non-coplanar geometry to three equivalent B(2) atoms. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. In the fifth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. Br(1) is bonded in a distorted T-shaped geometry to three equivalent Fe(1) atoms.
Fe3B7O13Br crystallizes in the trigonal R3c space group. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one Br(1) atom to form distorted FeBrO4 trigonal bipyramids that share corners with three equivalent B(2)O4 tetrahedra, corners with four equivalent B(3)O4 tetrahedra, and corners with two equivalent Fe(1)BrO4 trigonal bipyramids. The Fe(1)-O(1) bond length is 2.12 Å. The Fe(1)-O(2) bond length is 2.16 Å. The Fe(1)-O(3) bond length is 2.14 Å. The Fe(1)-O(4) bond length is 2.07 Å. The Fe(1)-Br(1) bond length is 2.72 Å. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. All B(1)-O(1) bond lengths are 1.38 Å. In the second B site, B(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form BO4 tetrahedra that share corners with two equivalent B(2)O4 tetrahedra, corners with three equivalent B(3)O4 tetrahedra, and corners with three equivalent Fe(1)BrO4 trigonal bipyramids. The B(2)-O(2) bond length is 1.46 Å. The B(2)-O(3) bond length is 1.46 Å. The B(2)-O(4) bond length is 1.48 Å. The B(2)-O(5) bond length is 1.57 Å. In the third B site, B(3) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form BO4 tetrahedra that share corners with three equivalent B(2)O4 tetrahedra and corners with four equivalent Fe(1)BrO4 trigonal bipyramids. The B(3)-O(1) bond length is 1.51 Å. The B(3)-O(2) bond length is 1.47 Å. The B(3)-O(3) bond length is 1.47 Å. The B(3)-O(4) bond length is 1.48 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(1), and one B(3) atom. In the second O site, O(5) is bonded in a trigonal non-coplanar geometry to three equivalent B(2) atoms. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. In the fifth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one B(2), and one B(3) atom. Br(1) is bonded in a distorted T-shaped geometry to three equivalent Fe(1) atoms.