Fe6Ge6Ho crystallizes in the orthorhombic Cmcm space group. Ho(1) is bonded to four equivalent Fe(1), four equivalent Fe(2), four equivalent Fe(3), one Ge(4), two equivalent Ge(3), two equivalent Ge(5), and three equivalent Ge(1) atoms to form distorted HoFe12Ge8 hexagonal bipyramids that share corners with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids, faces with eight equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, and faces with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(3), two equivalent Ge(3), two equivalent Ge(4), and two equivalent Ge(5) atoms to form distorted FeHo2Fe4Ge6 cuboctahedra that share corners with four equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, edges with two equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, faces with four equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, and faces with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Ho(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(5) atoms. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(2), one Ge(1), one Ge(2), one Ge(3), one Ge(4), and two equivalent Ge(5) atoms. There are five inequivalent Ge sites. In the first Ge site, Ge(3) is bonded in a 8-coordinate geometry to two equivalent Ho(1), two equivalent Fe(3), and four equivalent Fe(1) atoms. In the second Ge site, Ge(4) is bonded in a 7-coordinate geometry to one Ho(1), two equivalent Fe(3), and four equivalent Fe(1) atoms. In the third Ge site, Ge(5) is bonded in a 8-coordinate geometry to one Ho(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and one Ge(5) atom. In the fourth Ge site, Ge(1) is bonded in a 9-coordinate geometry to three equivalent Ho(1), two equivalent Fe(3), and four equivalent Fe(2) atoms. In the fifth Ge site, Ge(2) is bonded in a 6-coordinate geometry to two equivalent Fe(3) and four equivalent Fe(2) atoms.
Fe6Ge6Ho crystallizes in the orthorhombic Cmcm space group. Ho(1) is bonded to four equivalent Fe(1), four equivalent Fe(2), four equivalent Fe(3), one Ge(4), two equivalent Ge(3), two equivalent Ge(5), and three equivalent Ge(1) atoms to form distorted HoFe12Ge8 hexagonal bipyramids that share corners with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids, faces with eight equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, and faces with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids. All Ho(1)-Fe(1) bond lengths are 3.25 Å. All Ho(1)-Fe(2) bond lengths are 3.28 Å. All Ho(1)-Fe(3) bond lengths are 3.27 Å. The Ho(1)-Ge(4) bond length is 2.98 Å. Both Ho(1)-Ge(3) bond lengths are 2.96 Å. Both Ho(1)-Ge(5) bond lengths are 2.82 Å. There are two shorter (2.96 Å) and one longer (2.98 Å) Ho(1)-Ge(1) bond length. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(3), two equivalent Ge(3), two equivalent Ge(4), and two equivalent Ge(5) atoms to form distorted FeHo2Fe4Ge6 cuboctahedra that share corners with four equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, edges with two equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, faces with four equivalent Fe(1)Ho2Fe4Ge6 cuboctahedra, and faces with four equivalent Ho(1)Fe12Ge8 hexagonal bipyramids. Both Fe(1)-Fe(1) bond lengths are 2.55 Å. Both Fe(1)-Fe(3) bond lengths are 2.55 Å. Both Fe(1)-Ge(3) bond lengths are 2.50 Å. Both Fe(1)-Ge(4) bond lengths are 2.53 Å. Both Fe(1)-Ge(5) bond lengths are 2.68 Å. In the second Fe site, Fe(2) is bonded in a 12-coordinate geometry to two equivalent Ho(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Ge(1), two equivalent Ge(2), and two equivalent Ge(5) atoms. Both Fe(2)-Fe(2) bond lengths are 2.55 Å. Both Fe(2)-Fe(3) bond lengths are 2.55 Å. Both Fe(2)-Ge(1) bond lengths are 2.51 Å. Both Fe(2)-Ge(2) bond lengths are 2.51 Å. Both Fe(2)-Ge(5) bond lengths are 2.66 Å. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(2), one Ge(1), one Ge(2), one Ge(3), one Ge(4), and two equivalent Ge(5) atoms. The Fe(3)-Ge(1) bond length is 2.51 Å. The Fe(3)-Ge(2) bond length is 2.51 Å. The Fe(3)-Ge(3) bond length is 2.54 Å. The Fe(3)-Ge(4) bond length is 2.48 Å. Both Fe(3)-Ge(5) bond lengths are 2.67 Å. There are five inequivalent Ge sites. In the first Ge site, Ge(3) is bonded in a 8-coordinate geometry to two equivalent Ho(1), two equivalent Fe(3), and four equivalent Fe(1) atoms. In the second Ge site, Ge(4) is bonded in a 7-coordinate geometry to one Ho(1), two equivalent Fe(3), and four equivalent Fe(1) atoms. In the third Ge site, Ge(5) is bonded in a 8-coordinate geometry to one Ho(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), and one Ge(5) atom. The Ge(5)-Ge(5) bond length is 2.50 Å. In the fourth Ge site, Ge(1) is bonded in a 9-coordinate geometry to three equivalent Ho(1), two equivalent Fe(3), and four equivalent Fe(2) atoms. In the fifth Ge site, Ge(2) is bonded in a 6-coordinate geometry to two equivalent Fe(3) and four equivalent Fe(2) atoms.