Fe2BO4 crystallizes in the monoclinic Pc space group. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(3), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 57-64°. In the second Fe site, Fe(2) is bonded to one O(11), one O(12), one O(14), one O(3), one O(4), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 59-66°. In the third Fe site, Fe(3) is bonded to one O(11), one O(13), one O(14), one O(16), one O(5), and one O(6) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 54-60°. In the fourth Fe site, Fe(4) is bonded to one O(13), one O(15), one O(16), one O(6), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 54-66°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(6) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 53-61°. In the seventh Fe site, Fe(7) is bonded to one O(13), one O(14), one O(3), one O(5), one O(6), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 57-66°. In the eighth Fe site, Fe(8) is bonded to one O(14), one O(15), one O(16), one O(5), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 59-65°. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(16), one O(4), and one O(7) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(12), one O(15), and one O(8) atom. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(13) atom. In the fourth B site, B(4) is bonded in a trigonal planar geometry to one O(2), one O(5), and one O(9) atom. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(5), one Fe(6), and one B(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(5), and one B(4) atom. In the third O site, O(3) is bonded to one Fe(1), one Fe(2), one Fe(6), and one Fe(7) atom to form distorted edge-sharing OFe4 trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Fe(2), one Fe(5), one Fe(6), and one B(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(7), one Fe(8), and one B(4) atom. In the sixth O site, O(6) is bonded to one Fe(3), one Fe(4), one Fe(6), and one Fe(7) atom to form a mixture of distorted edge and corner-sharing OFe4 tetrahedra. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(8), and one B(1) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Fe(4), one Fe(7), one Fe(8), and one B(2) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(5), and one B(4) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(5), and one B(3) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Fe(2), one Fe(3), one Fe(5), and one Fe(6) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(6), and one B(2) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(4), one Fe(7), and one B(3) atom. In the fourteenth O site, O(14) is bonded to one Fe(2), one Fe(3), one Fe(7), and one Fe(8) atom to form a mixture of distorted edge and corner-sharing OFe4 tetrahedra. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(8), and one B(2) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(4), one Fe(8), and one B(1) atom.
Fe2BO4 crystallizes in the monoclinic Pc space group. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(3), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 57-64°. The Fe(1)-O(1) bond length is 2.18 Å. The Fe(1)-O(10) bond length is 1.99 Å. The Fe(1)-O(12) bond length is 2.15 Å. The Fe(1)-O(2) bond length is 2.00 Å. The Fe(1)-O(3) bond length is 1.94 Å. The Fe(1)-O(9) bond length is 2.14 Å. In the second Fe site, Fe(2) is bonded to one O(11), one O(12), one O(14), one O(3), one O(4), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 59-66°. The Fe(2)-O(11) bond length is 2.18 Å. The Fe(2)-O(12) bond length is 2.29 Å. The Fe(2)-O(14) bond length is 2.07 Å. The Fe(2)-O(3) bond length is 2.15 Å. The Fe(2)-O(4) bond length is 2.26 Å. The Fe(2)-O(9) bond length is 2.15 Å. In the third Fe site, Fe(3) is bonded to one O(11), one O(13), one O(14), one O(16), one O(5), and one O(6) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 54-60°. The Fe(3)-O(11) bond length is 1.99 Å. The Fe(3)-O(13) bond length is 2.22 Å. The Fe(3)-O(14) bond length is 1.96 Å. The Fe(3)-O(16) bond length is 2.12 Å. The Fe(3)-O(5) bond length is 2.14 Å. The Fe(3)-O(6) bond length is 2.03 Å. In the fourth Fe site, Fe(4) is bonded to one O(13), one O(15), one O(16), one O(6), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 53-66°. The Fe(4)-O(13) bond length is 2.15 Å. The Fe(4)-O(15) bond length is 1.99 Å. The Fe(4)-O(16) bond length is 2.15 Å. The Fe(4)-O(6) bond length is 1.98 Å. The Fe(4)-O(7) bond length is 1.99 Å. The Fe(4)-O(8) bond length is 2.10 Å. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), and one O(9) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 54-66°. The Fe(5)-O(1) bond length is 2.31 Å. The Fe(5)-O(10) bond length is 2.14 Å. The Fe(5)-O(11) bond length is 2.04 Å. The Fe(5)-O(2) bond length is 2.16 Å. The Fe(5)-O(4) bond length is 2.15 Å. The Fe(5)-O(9) bond length is 2.29 Å. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(11), one O(12), one O(3), one O(4), and one O(6) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 53-61°. The Fe(6)-O(1) bond length is 2.11 Å. The Fe(6)-O(11) bond length is 1.99 Å. The Fe(6)-O(12) bond length is 2.16 Å. The Fe(6)-O(3) bond length is 1.98 Å. The Fe(6)-O(4) bond length is 2.18 Å. The Fe(6)-O(6) bond length is 2.01 Å. In the seventh Fe site, Fe(7) is bonded to one O(13), one O(14), one O(3), one O(5), one O(6), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 57-66°. The Fe(7)-O(13) bond length is 2.26 Å. The Fe(7)-O(14) bond length is 2.08 Å. The Fe(7)-O(3) bond length is 2.11 Å. The Fe(7)-O(5) bond length is 2.27 Å. The Fe(7)-O(6) bond length is 2.18 Å. The Fe(7)-O(8) bond length is 2.17 Å. In the eighth Fe site, Fe(8) is bonded to one O(14), one O(15), one O(16), one O(5), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing FeO6 octahedra. The corner-sharing octahedral tilt angles range from 59-65°. The Fe(8)-O(14) bond length is 2.03 Å. The Fe(8)-O(15) bond length is 2.14 Å. The Fe(8)-O(16) bond length is 2.33 Å. The Fe(8)-O(5) bond length is 2.15 Å. The Fe(8)-O(7) bond length is 2.15 Å. The Fe(8)-O(8) bond length is 2.33 Å. There are four inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(16), one O(4), and one O(7) atom. The B(1)-O(16) bond length is 1.41 Å. The B(1)-O(4) bond length is 1.39 Å. The B(1)-O(7) bond length is 1.37 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(12), one O(15), and one O(8) atom. The B(2)-O(12) bond length is 1.40 Å. The B(2)-O(15) bond length is 1.38 Å. The B(2)-O(8) bond length is 1.40 Å. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(13) atom. The B(3)-O(1) bond length is 1.40 Å. The B(3)-O(10) bond length is 1.37 Å. The B(3)-O(13) bond length is 1.40 Å. In the fourth B site, B(4) is bonded in a trigonal planar geometry to one O(2), one O(5), and one O(9) atom. The B(4)-O(2) bond length is 1.38 Å. The B(4)-O(5) bond length is 1.40 Å. The B(4)-O(9) bond length is 1.40 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(5), one Fe(6), and one B(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(5), and one B(4) atom. In the third O site, O(3) is bonded to one Fe(1), one Fe(2), one Fe(6), and one Fe(7) atom to form distorted edge-sharing OFe4 trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Fe(2), one Fe(5), one Fe(6), and one B(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(7), one Fe(8), and one B(4) atom. In the sixth O site, O(6) is bonded to one Fe(3), one Fe(4), one Fe(6), and one Fe(7) atom to form a mixture of distorted edge and corner-sharing OFe4 tetrahedra. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(8), and one B(1) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Fe(4), one Fe(7), one Fe(8), and one B(2) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(5), and one B(4) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(5), and one B(3) atom. In the eleventh O site, O(11) is bonded in a distorted rectangular see-saw-like geometry to one Fe(2), one Fe(3), one Fe(5), and one Fe(6) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(6), and one B(2) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(4), one Fe(7), and one B(3) atom. In the fourteenth O site, O(14) is bonded to one Fe(2), one Fe(3), one Fe(7), and one Fe(8) atom to form a mixture of distorted edge and corner-sharing OFe4 tetrahedra. In the fifteenth O site, O(15) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(8), and one B(2) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Fe(3), one Fe(4), one Fe(8), and one B(1) atom.