The material described by Mg3Ho is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen equivalent Mg(1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. In the second Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1,1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. In the third Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1,1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. Ho(1) is bonded to twelve Mg(1,1,1) atoms to form HoMg12 cuboctahedra that share corners with six equivalent Ho(1)Mg12 cuboctahedra; corners with twelve equivalent Mg(1)Ho4Mg8 cuboctahedra; edges with eighteen Mg(1,1,1)Ho4Mg8 cuboctahedra; faces with eight equivalent Ho(1)Mg12 cuboctahedra; and faces with twelve Mg(1,1,1)Ho4Mg8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HoMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.633
_cell_length_b   6.633
_cell_length_c   5.158
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   196.529
_cell_formula_units_Z   2
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  0.667  0.333  0.250  1.0
  Ho  Ho1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.164  0.327  0.250  1.0
  Mg  Mg3  1  0.164  0.836  0.250  1.0
  Mg  Mg4  1  0.673  0.836  0.250  1.0
  Mg  Mg5  1  0.327  0.164  0.750  1.0
  Mg  Mg6  1  0.836  0.164  0.750  1.0
  Mg  Mg7  1  0.836  0.673  0.750  1.0
[/CIF]
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The material described by Mg3Ho is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen equivalent Mg(1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. In the second Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1,1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. In the third Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Ho(1) atoms to form MgHo4Mg8 cuboctahedra that share corners with four equivalent Ho(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1,1)Ho4Mg8 cuboctahedra; edges with six equivalent Ho(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Ho4Mg8 cuboctahedra; faces with four equivalent Ho(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1,1)Ho4Mg8 cuboctahedra. Ho(1) is bonded to twelve Mg(1,1,1) atoms to form HoMg12 cuboctahedra that share corners with six equivalent Ho(1)Mg12 cuboctahedra; corners with twelve equivalent Mg(1)Ho4Mg8 cuboctahedra; edges with eighteen Mg(1,1,1)Ho4Mg8 cuboctahedra; faces with eight equivalent Ho(1)Mg12 cuboctahedra; and faces with twelve Mg(1,1,1)Ho4Mg8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_HoMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.633
_cell_length_b   6.633
_cell_length_c   5.158
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   196.529
_cell_formula_units_Z   2
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  0.667  0.333  0.250  1.0
  Ho  Ho1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.164  0.327  0.250  1.0
  Mg  Mg3  1  0.164  0.836  0.250  1.0
  Mg  Mg4  1  0.673  0.836  0.250  1.0
  Mg  Mg5  1  0.327  0.164  0.750  1.0
  Mg  Mg6  1  0.836  0.164  0.750  1.0
  Mg  Mg7  1  0.836  0.673  0.750  1.0
[/CIF]
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