The compound described by Mg5Sb crystallizes in the trigonal R32 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(2), six equivalent Mg(1), and two equivalent Sb(1) atoms to form distorted MgMg10Sb2 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg10Sb2 cuboctahedra, edges with four equivalent Sb(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg10Sb2 cuboctahedra, edges with eight equivalent Mg(2)Mg9Sb3 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, faces with eight equivalent Mg(1)Mg10Sb2 cuboctahedra, and faces with eight equivalent Mg(2)Mg9Sb3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Sb(1) atoms to form distorted MgMg9Sb3 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with six equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra, faces with four equivalent Mg(2)Mg9Sb3 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra. Sb(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form SbMg12 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with six equivalent Sb(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra, faces with eight equivalent Mg(2)Mg9Sb3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg5Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.125
_cell_length_b   6.125
_cell_length_c   6.125
_cell_angle_alpha   53.897
_cell_angle_beta   53.897
_cell_angle_gamma   53.897
_symmetry_Int_Tables_number   1
_cell_volume   139.317
_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
  Mg  Mg0  1  0.000  0.667  0.333  1.0
  Mg  Mg1  1  0.833  0.833  0.833  1.0
  Mg  Mg2  1  0.667  0.333  0.000  1.0
  Mg  Mg3  1  0.333  0.000  0.667  1.0
  Mg  Mg4  1  0.167  0.167  0.167  1.0
  Sb  Sb5  1  0.500  0.500  0.500  1.0
[/CIF]
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The compound described by Mg5Sb crystallizes in the trigonal R32 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Mg(2), six equivalent Mg(1), and two equivalent Sb(1) atoms to form distorted MgMg10Sb2 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg10Sb2 cuboctahedra, edges with four equivalent Sb(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Mg10Sb2 cuboctahedra, edges with eight equivalent Mg(2)Mg9Sb3 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, faces with eight equivalent Mg(1)Mg10Sb2 cuboctahedra, and faces with eight equivalent Mg(2)Mg9Sb3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Sb(1) atoms to form distorted MgMg9Sb3 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with six equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra, faces with four equivalent Mg(2)Mg9Sb3 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra. Sb(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form SbMg12 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Sb3 cuboctahedra, edges with six equivalent Sb(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra, faces with eight equivalent Mg(2)Mg9Sb3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg10Sb2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg5Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.125
_cell_length_b   6.125
_cell_length_c   6.125
_cell_angle_alpha   53.897
_cell_angle_beta   53.897
_cell_angle_gamma   53.897
_symmetry_Int_Tables_number   1
_cell_volume   139.317
_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
  Mg  Mg0  1  0.000  0.667  0.333  1.0
  Mg  Mg1  1  0.833  0.833  0.833  1.0
  Mg  Mg2  1  0.667  0.333  0.000  1.0
  Mg  Mg3  1  0.333  0.000  0.667  1.0
  Mg  Mg4  1  0.167  0.167  0.167  1.0
  Sb  Sb5  1  0.500  0.500  0.500  1.0
[/CIF]
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