Ho2FeSi4 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 13-coordinate geometry to two equivalent Fe(1), one Si(3), two equivalent Si(1), four equivalent Si(2), and four equivalent Si(4) atoms. In the second Ho site, Ho(2) is bonded in a 13-coordinate geometry to two equivalent Fe(1), one Si(4), two equivalent Si(2), four equivalent Si(1), and four equivalent Si(3) atoms. Fe(1) is bonded in a 8-coordinate geometry to two equivalent Ho(1), two equivalent Ho(2), two equivalent Si(3), and two equivalent Si(4) atoms. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ho(1), four equivalent Ho(2), one Si(3), and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Ho(2), four equivalent Ho(1), one Si(4), and two equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Ho(1), four equivalent Ho(2), two equivalent Fe(1), and one Si(1) atom. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to one Ho(2), four equivalent Ho(1), two equivalent Fe(1), and one Si(2) atom.
Ho2FeSi4 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 13-coordinate geometry to two equivalent Fe(1), one Si(3), two equivalent Si(1), four equivalent Si(2), and four equivalent Si(4) atoms. Both Ho(1)-Fe(1) bond lengths are 3.06 Å. The Ho(1)-Si(3) bond length is 3.24 Å. Both Ho(1)-Si(1) bond lengths are 3.06 Å. All Ho(1)-Si(2) bond lengths are 3.00 Å. All Ho(1)-Si(4) bond lengths are 3.15 Å. In the second Ho site, Ho(2) is bonded in a 13-coordinate geometry to two equivalent Fe(1), one Si(4), two equivalent Si(2), four equivalent Si(1), and four equivalent Si(3) atoms. Both Ho(2)-Fe(1) bond lengths are 2.98 Å. The Ho(2)-Si(4) bond length is 3.14 Å. Both Ho(2)-Si(2) bond lengths are 3.18 Å. All Ho(2)-Si(1) bond lengths are 3.05 Å. All Ho(2)-Si(3) bond lengths are 3.11 Å. Fe(1) is bonded in a 8-coordinate geometry to two equivalent Ho(1), two equivalent Ho(2), two equivalent Si(3), and two equivalent Si(4) atoms. Both Fe(1)-Si(3) bond lengths are 2.21 Å. Both Fe(1)-Si(4) bond lengths are 2.19 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Ho(1), four equivalent Ho(2), one Si(3), and two equivalent Si(2) atoms. The Si(1)-Si(3) bond length is 2.45 Å. Both Si(1)-Si(2) bond lengths are 2.39 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Ho(2), four equivalent Ho(1), one Si(4), and two equivalent Si(1) atoms. The Si(2)-Si(4) bond length is 2.39 Å. In the third Si site, Si(3) is bonded in a 8-coordinate geometry to one Ho(1), four equivalent Ho(2), two equivalent Fe(1), and one Si(1) atom. In the fourth Si site, Si(4) is bonded in a 8-coordinate geometry to one Ho(2), four equivalent Ho(1), two equivalent Fe(1), and one Si(2) atom.