Ho2(Fe3Si)3 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 18-coordinate geometry to two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(1), four equivalent Fe(2), two equivalent Si(1), and two equivalent Si(2) atoms. In the second Ho site, Ho(2) is bonded in a 18-coordinate geometry to one Fe(5), two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(3), four equivalent Fe(4), one Si(1), and four equivalent Si(2) atoms. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), one Si(1), and two equivalent Si(2) atoms. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to one Ho(2), two equivalent Ho(1), one Fe(5), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Si(2) atoms. In the third Fe site, Fe(3) is bonded in a 3-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(4), two equivalent Fe(1), two equivalent Fe(2), one Si(2), and two equivalent Si(1) atoms. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(3), one Fe(4), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), and one Si(2) atom. In the fifth Fe site, Fe(5) is bonded in a 9-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(2), and four equivalent Fe(4) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(1), and four equivalent Fe(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(3), one Fe(4), two equivalent Fe(1), and two equivalent Fe(2) atoms.
Ho2(Fe3Si)3 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 18-coordinate geometry to two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(5), four equivalent Fe(1), four equivalent Fe(2), two equivalent Si(1), and two equivalent Si(2) atoms. Both Ho(1)-Fe(3) bond lengths are 3.15 Å. Both Ho(1)-Fe(4) bond lengths are 3.10 Å. Both Ho(1)-Fe(5) bond lengths are 2.86 Å. All Ho(1)-Fe(1) bond lengths are 3.24 Å. All Ho(1)-Fe(2) bond lengths are 3.18 Å. Both Ho(1)-Si(1) bond lengths are 2.95 Å. Both Ho(1)-Si(2) bond lengths are 2.81 Å. In the second Ho site, Ho(2) is bonded in a 18-coordinate geometry to one Fe(5), two equivalent Fe(1), two equivalent Fe(2), four equivalent Fe(3), four equivalent Fe(4), one Si(1), and four equivalent Si(2) atoms. The Ho(2)-Fe(5) bond length is 2.80 Å. Both Ho(2)-Fe(1) bond lengths are 3.02 Å. Both Ho(2)-Fe(2) bond lengths are 3.06 Å. All Ho(2)-Fe(3) bond lengths are 3.23 Å. All Ho(2)-Fe(4) bond lengths are 3.11 Å. The Ho(2)-Si(1) bond length is 2.87 Å. All Ho(2)-Si(2) bond lengths are 2.88 Å. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 12-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), one Si(1), and two equivalent Si(2) atoms. There is one shorter (2.46 Å) and one longer (2.61 Å) Fe(1)-Fe(2) bond length. Both Fe(1)-Fe(3) bond lengths are 2.59 Å. Both Fe(1)-Fe(4) bond lengths are 2.54 Å. The Fe(1)-Si(1) bond length is 2.40 Å. Both Fe(1)-Si(2) bond lengths are 2.40 Å. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to one Ho(2), two equivalent Ho(1), one Fe(5), two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Si(2) atoms. The Fe(2)-Fe(5) bond length is 2.39 Å. Both Fe(2)-Fe(3) bond lengths are 2.56 Å. Both Fe(2)-Fe(4) bond lengths are 2.65 Å. Both Fe(2)-Si(2) bond lengths are 2.38 Å. In the third Fe site, Fe(3) is bonded in a 3-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(4), two equivalent Fe(1), two equivalent Fe(2), one Si(2), and two equivalent Si(1) atoms. The Fe(3)-Fe(4) bond length is 2.48 Å. The Fe(3)-Si(2) bond length is 2.35 Å. Both Fe(3)-Si(1) bond lengths are 2.40 Å. In the fourth Fe site, Fe(4) is bonded in a 12-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(3), one Fe(4), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(5), and one Si(2) atom. The Fe(4)-Fe(4) bond length is 2.54 Å. Both Fe(4)-Fe(5) bond lengths are 2.39 Å. The Fe(4)-Si(2) bond length is 2.33 Å. In the fifth Fe site, Fe(5) is bonded in a 9-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(2), and four equivalent Fe(4) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Ho(2), two equivalent Ho(1), two equivalent Fe(1), and four equivalent Fe(3) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Ho(1), two equivalent Ho(2), one Fe(3), one Fe(4), two equivalent Fe(1), and two equivalent Fe(2) atoms.