The crystal structure described by Mg3Sb is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted square co-planar geometry to eight equivalent Mg(2) and four equivalent Sb(1) atoms. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Sb(1) atoms to form distorted MgMg8Sb4 cuboctahedra that share corners with twelve equivalent Mg(2)Mg8Sb4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Sb4 cuboctahedra, edges with eight equivalent Sb(1)Mg12 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Sb4 cuboctahedra. Sb(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form SbMg12 cuboctahedra that share corners with four equivalent Sb(1)Mg12 cuboctahedra, edges with eight equivalent Sb(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Mg8Sb4 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Sb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.694
_cell_length_b   5.694
_cell_length_c   5.694
_cell_angle_alpha   134.502
_cell_angle_beta   134.502
_cell_angle_gamma   66.305
_symmetry_Int_Tables_number   1
_cell_volume   92.426
_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  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.250  0.750  0.500  1.0
  Mg  Mg2  1  0.750  0.250  0.500  1.0
  Sb  Sb3  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by Mg3Sb is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted square co-planar geometry to eight equivalent Mg(2) and four equivalent Sb(1) atoms. In the second Mg site, Mg(2) is bonded to four equivalent Mg(1), four equivalent Mg(2), and four equivalent Sb(1) atoms to form distorted MgMg8Sb4 cuboctahedra that share corners with twelve equivalent Mg(2)Mg8Sb4 cuboctahedra, edges with eight equivalent Mg(2)Mg8Sb4 cuboctahedra, edges with eight equivalent Sb(1)Mg12 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with ten equivalent Mg(2)Mg8Sb4 cuboctahedra. Sb(1) is bonded to four equivalent Mg(1) and eight equivalent Mg(2) atoms to form SbMg12 cuboctahedra that share corners with four equivalent Sb(1)Mg12 cuboctahedra, edges with eight equivalent Sb(1)Mg12 cuboctahedra, edges with sixteen equivalent Mg(2)Mg8Sb4 cuboctahedra, faces with four equivalent Sb(1)Mg12 cuboctahedra, and faces with eight equivalent Mg(2)Mg8Sb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.694
_cell_length_b   5.694
_cell_length_c   5.694
_cell_angle_alpha   134.502
_cell_angle_beta   134.502
_cell_angle_gamma   66.305
_symmetry_Int_Tables_number   1
_cell_volume   92.426
_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  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.250  0.750  0.500  1.0
  Mg  Mg2  1  0.750  0.250  0.500  1.0
  Sb  Sb3  1  0.000  0.000  0.000  1.0
[/CIF]
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