MgFeBO4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. Fe(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Fe(1), and one B(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(1), and one B(1) atom. In the third O site, O(3) is bonded to one Mg(1) and three equivalent Fe(1) atoms to form a mixture of edge and corner-sharing OMgFe3 tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one B(1) atom.
MgFeBO4 crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. The Mg(1)-O(1) bond length is 2.15 Å. The Mg(1)-O(3) bond length is 2.06 Å. Both Mg(1)-O(2) bond lengths are 2.18 Å. Both Mg(1)-O(4) bond lengths are 2.02 Å. Fe(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-64°. The Fe(1)-O(2) bond length is 2.07 Å. Both Fe(1)-O(1) bond lengths are 2.16 Å. There are two shorter (2.01 Å) and one longer (2.03 Å) Fe(1)-O(3) bond length. B(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(4) atom. The B(1)-O(1) bond length is 1.42 Å. The B(1)-O(2) bond length is 1.41 Å. The B(1)-O(4) bond length is 1.35 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Fe(1), and one B(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(1), and one B(1) atom. In the third O site, O(3) is bonded to one Mg(1) and three equivalent Fe(1) atoms to form a mixture of edge and corner-sharing OMgFe3 tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one B(1) atom.