SmFeB4 crystallizes in the orthorhombic Pbam space group. Sm(1) is bonded in a 14-coordinate geometry to two equivalent B(2), four equivalent B(1), four equivalent B(3), and four equivalent B(4) atoms. Fe(1) is bonded in a 10-coordinate geometry to two equivalent B(1), two equivalent B(3), two equivalent B(4), and four equivalent B(2) atoms. There are four inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(2), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), four equivalent Fe(1), one B(1), one B(2), and one B(4) atom. In the third B site, B(3) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(4), and two equivalent B(1) atoms. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(2), one B(3), and one B(4) atom.
SmFeB4 crystallizes in the orthorhombic Pbam space group. Sm(1) is bonded in a 14-coordinate geometry to two equivalent B(2), four equivalent B(1), four equivalent B(3), and four equivalent B(4) atoms. Both Sm(1)-B(2) bond lengths are 2.64 Å. There are two shorter (2.70 Å) and two longer (2.76 Å) Sm(1)-B(1) bond lengths. There are two shorter (2.74 Å) and two longer (2.76 Å) Sm(1)-B(3) bond lengths. There are two shorter (2.72 Å) and two longer (2.75 Å) Sm(1)-B(4) bond lengths. Fe(1) is bonded in a 10-coordinate geometry to two equivalent B(1), two equivalent B(3), two equivalent B(4), and four equivalent B(2) atoms. Both Fe(1)-B(1) bond lengths are 2.31 Å. Both Fe(1)-B(3) bond lengths are 2.28 Å. Both Fe(1)-B(4) bond lengths are 2.30 Å. All Fe(1)-B(2) bond lengths are 2.29 Å. There are four inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(2), and two equivalent B(3) atoms. The B(1)-B(2) bond length is 1.73 Å. There is one shorter (1.79 Å) and one longer (1.91 Å) B(1)-B(3) bond length. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Sm(1), four equivalent Fe(1), one B(1), one B(2), and one B(4) atom. The B(2)-B(2) bond length is 1.70 Å. The B(2)-B(4) bond length is 1.74 Å. In the third B site, B(3) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(4), and two equivalent B(1) atoms. The B(3)-B(4) bond length is 1.79 Å. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to four equivalent Sm(1), two equivalent Fe(1), one B(2), one B(3), and one B(4) atom. The B(4)-B(4) bond length is 1.85 Å.