The material described by Mg3Sb is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to eight equivalent Mg(1) and four equivalent Sb(1) atoms to form distorted MgMg8Sb4 cuboctahedra that share corners with four equivalent Sb(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(1)Mg8Sb4 cuboctahedra, edges with six equivalent Sb(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with sixteen equivalent Mg(1)Mg8Sb4 cuboctahedra. Sb(1) is bonded to twelve equivalent Mg(1) atoms to form SbMg12 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra, edges with eighteen equivalent Mg(1)Mg8Sb4 cuboctahedra, faces with eight equivalent Sb(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.259
_cell_length_b   6.259
_cell_length_c   5.440
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   184.524
_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
  Mg  Mg0  1  0.329  0.165  0.250  1.0
  Mg  Mg1  1  0.835  0.165  0.250  1.0
  Mg  Mg2  1  0.835  0.671  0.250  1.0
  Mg  Mg3  1  0.671  0.835  0.750  1.0
  Mg  Mg4  1  0.165  0.329  0.750  1.0
  Mg  Mg5  1  0.165  0.835  0.750  1.0
  Sb  Sb6  1  0.333  0.667  0.250  1.0
  Sb  Sb7  1  0.667  0.333  0.750  1.0
[/CIF]
.
The material described by Mg3Sb is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. Mg(1) is bonded to eight equivalent Mg(1) and four equivalent Sb(1) atoms to form distorted MgMg8Sb4 cuboctahedra that share corners with four equivalent Sb(1)Mg12 cuboctahedra, corners with fourteen equivalent Mg(1)Mg8Sb4 cuboctahedra, edges with six equivalent Sb(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with sixteen equivalent Mg(1)Mg8Sb4 cuboctahedra. Sb(1) is bonded to twelve equivalent Mg(1) atoms to form SbMg12 cuboctahedra that share corners with six equivalent Sb(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra, edges with eighteen equivalent Mg(1)Mg8Sb4 cuboctahedra, faces with eight equivalent Sb(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Sb4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.259
_cell_length_b   6.259
_cell_length_c   5.440
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   184.524
_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
  Mg  Mg0  1  0.329  0.165  0.250  1.0
  Mg  Mg1  1  0.835  0.165  0.250  1.0
  Mg  Mg2  1  0.835  0.671  0.250  1.0
  Mg  Mg3  1  0.671  0.835  0.750  1.0
  Mg  Mg4  1  0.165  0.329  0.750  1.0
  Mg  Mg5  1  0.165  0.835  0.750  1.0
  Sb  Sb6  1  0.333  0.667  0.250  1.0
  Sb  Sb7  1  0.667  0.333  0.750  1.0
[/CIF]
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