The material described by SrMg6Sb crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sb(1) atoms to form SrMg10Sb2 cuboctahedra that share corners with four equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with eight equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sb(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Sb(1) atoms to form distorted MgSr2Mg8Sb2 cuboctahedra that share corners with four equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with four equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sr(1)Mg10Sb2 cuboctahedra, edges with two equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sb(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(4), and two equivalent Sb(1) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sb(1) atoms. Sb(1) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted SbSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with six equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sr(1)Mg10Sb2 cuboctahedra, edges with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. is represented by the CIF file [CIF]
data_SrMg6Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.430
_cell_length_b   6.451
_cell_length_c   6.791
_cell_angle_alpha   118.355
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   209.353
_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  0.667  0.838  1.0
  Mg  Mg1  1  0.500  0.170  0.838  1.0
  Mg  Mg2  1  0.000  0.817  0.152  1.0
  Mg  Mg3  1  0.000  0.334  0.152  1.0
  Mg  Mg4  1  0.000  0.343  0.686  1.0
  Mg  Mg5  1  0.000  0.836  0.671  1.0
  Sb  Sb6  1  0.500  0.661  0.323  1.0
  Sr  Sr7  1  0.500  0.171  0.342  1.0
[/CIF]
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The material described by SrMg6Sb crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sb(1) atoms to form SrMg10Sb2 cuboctahedra that share corners with four equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with eight equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sb(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Sb(1) atoms to form distorted MgSr2Mg8Sb2 cuboctahedra that share corners with four equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with four equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sr(1)Mg10Sb2 cuboctahedra, edges with two equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sb(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(4), and two equivalent Sb(1) atoms. In the third Mg site, Mg(3) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(2), two equivalent Mg(4), and four equivalent Mg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Sb(1) atoms. Sb(1) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form distorted SbSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Mg10Sb2 cuboctahedra, corners with six equivalent Sb(1)Sr2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, edges with two equivalent Sr(1)Mg10Sb2 cuboctahedra, edges with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr2Mg8Sb2 cuboctahedra. is represented by the CIF file [CIF]
data_SrMg6Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.430
_cell_length_b   6.451
_cell_length_c   6.791
_cell_angle_alpha   118.355
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   209.353
_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  0.667  0.838  1.0
  Mg  Mg1  1  0.500  0.170  0.838  1.0
  Mg  Mg2  1  0.000  0.817  0.152  1.0
  Mg  Mg3  1  0.000  0.334  0.152  1.0
  Mg  Mg4  1  0.000  0.343  0.686  1.0
  Mg  Mg5  1  0.000  0.836  0.671  1.0
  Sb  Sb6  1  0.500  0.661  0.323  1.0
  Sr  Sr7  1  0.500  0.171  0.342  1.0
[/CIF]
.