The compound described by MgHo3 crystallizes in the tetragonal P4/mmm space group. Mg(1) is bonded in a distorted body-centered cubic geometry to eight equivalent Ho(1) atoms. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Mg(1), four equivalent Ho(1), and four equivalent Ho(2) atoms to form distorted HoHo8Mg4 cuboctahedra that share corners with twelve equivalent Ho(1)Ho8Mg4 cuboctahedra, edges with eight equivalent Ho(2)Ho12 cuboctahedra, edges with eight equivalent Ho(1)Ho8Mg4 cuboctahedra, faces with four equivalent Ho(2)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Ho8Mg4 cuboctahedra. In the second Ho site, Ho(2) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form HoHo12 cuboctahedra that share corners with four equivalent Ho(2)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Ho8Mg4 cuboctahedra, faces with eight equivalent Ho(2)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Ho8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Ho3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.556
_cell_length_b   3.556
_cell_length_c   9.249
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   116.969
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ho  Ho0  1  0.500  0.500  0.765  1.0
  Ho  Ho1  1  0.000  0.000  0.500  1.0
  Ho  Ho2  1  0.500  0.500  0.235  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
.
The compound described by MgHo3 crystallizes in the tetragonal P4/mmm space group. Mg(1) is bonded in a distorted body-centered cubic geometry to eight equivalent Ho(1) atoms. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to four equivalent Mg(1), four equivalent Ho(1), and four equivalent Ho(2) atoms to form distorted HoHo8Mg4 cuboctahedra that share corners with twelve equivalent Ho(1)Ho8Mg4 cuboctahedra, edges with eight equivalent Ho(2)Ho12 cuboctahedra, edges with eight equivalent Ho(1)Ho8Mg4 cuboctahedra, faces with four equivalent Ho(2)Ho12 cuboctahedra, and faces with ten equivalent Ho(1)Ho8Mg4 cuboctahedra. In the second Ho site, Ho(2) is bonded to four equivalent Ho(2) and eight equivalent Ho(1) atoms to form HoHo12 cuboctahedra that share corners with four equivalent Ho(2)Ho12 cuboctahedra, edges with sixteen equivalent Ho(1)Ho8Mg4 cuboctahedra, faces with eight equivalent Ho(2)Ho12 cuboctahedra, and faces with eight equivalent Ho(1)Ho8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Ho3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.556
_cell_length_b   3.556
_cell_length_c   9.249
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   116.969
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Ho  Ho0  1  0.500  0.500  0.765  1.0
  Ho  Ho1  1  0.000  0.000  0.500  1.0
  Ho  Ho2  1  0.500  0.500  0.235  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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