HoFe6Ga6 crystallizes in the orthorhombic Fmmm space group. Ho(1) is bonded in a 20-coordinate geometry to four equivalent Fe(2), eight equivalent Fe(1), four equivalent Ga(1), and four equivalent Ga(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(2) is bonded to two equivalent Ho(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Ga(2) atoms to form distorted FeHo2Ga4Fe6 cuboctahedra that share corners with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with six equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, faces with two equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, faces with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, and faces with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. In the second Fe site, Fe(1) is bonded to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Ga(1), and four equivalent Ga(2) atoms to form distorted FeHo2Ga6Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with ten equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with two equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, edges with two equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, edges with three equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, faces with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, faces with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, and faces with seven equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to two equivalent Ho(1), four equivalent Fe(1), two equivalent Ga(1), and four equivalent Ga(2) atoms to form GaHo2Ga6Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with six equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, edges with four equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, faces with two equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, faces with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, and faces with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to one Ho(1), two equivalent Fe(2), four equivalent Fe(1), one Ga(2), and two equivalent Ga(1) atoms.
HoFe6Ga6 crystallizes in the orthorhombic Fmmm space group. Ho(1) is bonded in a 20-coordinate geometry to four equivalent Fe(2), eight equivalent Fe(1), four equivalent Ga(1), and four equivalent Ga(2) atoms. All Ho(1)-Fe(2) bond lengths are 3.34 Å. All Ho(1)-Fe(1) bond lengths are 3.15 Å. All Ho(1)-Ga(1) bond lengths are 3.26 Å. All Ho(1)-Ga(2) bond lengths are 3.02 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(2) is bonded to two equivalent Ho(1), two equivalent Fe(2), four equivalent Fe(1), and four equivalent Ga(2) atoms to form distorted FeHo2Ga4Fe6 cuboctahedra that share corners with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with six equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, faces with two equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, faces with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, and faces with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. Both Fe(2)-Fe(2) bond lengths are 2.59 Å. All Fe(2)-Fe(1) bond lengths are 2.48 Å. All Fe(2)-Ga(2) bond lengths are 2.53 Å. In the second Fe site, Fe(1) is bonded to two equivalent Ho(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Ga(1), and four equivalent Ga(2) atoms to form distorted FeHo2Ga6Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with ten equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with two equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, edges with two equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, edges with three equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, faces with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, faces with four equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, and faces with seven equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. There is one shorter (2.42 Å) and one longer (2.67 Å) Fe(1)-Fe(1) bond length. Both Fe(1)-Ga(1) bond lengths are 2.58 Å. There are a spread of Fe(1)-Ga(2) bond distances ranging from 2.69-2.93 Å. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to two equivalent Ho(1), four equivalent Fe(1), two equivalent Ga(1), and four equivalent Ga(2) atoms to form GaHo2Ga6Fe4 cuboctahedra that share corners with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, corners with six equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, corners with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, edges with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, edges with four equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra, faces with two equivalent Ga(1)Ho2Ga6Fe4 cuboctahedra, faces with four equivalent Fe(2)Ho2Ga4Fe6 cuboctahedra, and faces with eight equivalent Fe(1)Ho2Ga6Fe4 cuboctahedra. Both Ga(1)-Ga(1) bond lengths are 2.59 Å. All Ga(1)-Ga(2) bond lengths are 2.78 Å. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to one Ho(1), two equivalent Fe(2), four equivalent Fe(1), one Ga(2), and two equivalent Ga(1) atoms. The Ga(2)-Ga(2) bond length is 2.57 Å.