SmFe3(BO3)4 crystallizes in the trigonal R32 space group. Sm(1) is bonded in a 6-coordinate geometry to six equivalent O(3) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form edge-sharing FeO6 octahedra. There are two 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 in a distorted rectangular see-saw-like geometry to four equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one B(1) atom. In the second O site, O(2) is bonded in an L-shaped geometry to two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sm(1), one Fe(1), and two equivalent B(2) atoms.
SmFe3(BO3)4 crystallizes in the trigonal R32 space group. Sm(1) is bonded in a 6-coordinate geometry to six equivalent O(3) atoms. All Sm(1)-O(3) bond lengths are 2.71 Å. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form edge-sharing FeO6 octahedra. Both Fe(1)-O(1) bond lengths are 2.08 Å. Both Fe(1)-O(2) bond lengths are 1.87 Å. Both Fe(1)-O(3) bond lengths are 2.09 Å. There are two 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 in a distorted rectangular see-saw-like geometry to four equivalent O(3) atoms. There are two shorter (1.48 Å) and two longer (1.59 Å) B(2)-O(3) bond lengths. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one B(1) atom. In the second O site, O(2) is bonded in an L-shaped geometry to two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Sm(1), one Fe(1), and two equivalent B(2) atoms.