SmFeSi2 crystallizes in the monoclinic P2_1/m space group. Sm(1) is bonded in a 12-coordinate geometry to three equivalent Fe(1), three equivalent Si(2), and six equivalent Si(1) atoms. Fe(1) is bonded in a 5-coordinate geometry to three equivalent Sm(1), one Si(1), and four equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Sm(1), one Fe(1), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Sm(1), four equivalent Fe(1), and two equivalent Si(2) atoms.
SmFeSi2 crystallizes in the monoclinic P2_1/m space group. Sm(1) is bonded in a 12-coordinate geometry to three equivalent Fe(1), three equivalent Si(2), and six equivalent Si(1) atoms. There are two shorter (3.07 Å) and one longer (3.14 Å) Sm(1)-Fe(1) bond length. There is one shorter (2.90 Å) and two longer (3.02 Å) Sm(1)-Si(2) bond lengths. There are a spread of Sm(1)-Si(1) bond distances ranging from 3.01-3.25 Å. Fe(1) is bonded in a 5-coordinate geometry to three equivalent Sm(1), one Si(1), and four equivalent Si(2) atoms. The Fe(1)-Si(1) bond length is 2.29 Å. There are a spread of Fe(1)-Si(2) bond distances ranging from 2.25-2.34 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Sm(1), one Fe(1), and two equivalent Si(1) atoms. Both Si(1)-Si(1) bond lengths are 2.52 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Sm(1), four equivalent Fe(1), and two equivalent Si(2) atoms. Both Si(2)-Si(2) bond lengths are 2.51 Å.