The structure described by Mg23Sr6 crystallizes in the cubic Fm-3m space group. Sr(1) is bonded in a 12-coordinate geometry to four equivalent Mg(2), four equivalent Mg(3), and four equivalent Mg(4) atoms. There are four inequivalent Mg sites. In the first Mg site, Mg(4) is bonded in a distorted q6 geometry to three equivalent Sr(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Mg(4) atoms. In the second Mg site, Mg(1) is bonded in a body-centered cubic geometry to eight equivalent Mg(3) atoms. In the third Mg site, Mg(2) is bonded to four equivalent Sr(1), four equivalent Mg(3), and four equivalent Mg(4) atoms to form a mixture of corner and face-sharing MgSr4Mg8 cuboctahedra. In the fourth Mg site, Mg(3) is bonded in a 10-coordinate geometry to three equivalent Sr(1), one Mg(1), three equivalent Mg(2), and three equivalent Mg(4) atoms. is represented by the CIF card [CIF]
data_Sr6Mg23
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.509
_cell_length_b   10.509
_cell_length_c   10.509
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   820.691
_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
  Sr  Sr0  1  0.793  0.207  0.207  1.0
  Sr  Sr1  1  0.793  0.793  0.207  1.0
  Sr  Sr2  1  0.207  0.207  0.793  1.0
  Sr  Sr3  1  0.793  0.207  0.793  1.0
  Sr  Sr4  1  0.207  0.793  0.207  1.0
  Sr  Sr5  1  0.207  0.793  0.793  1.0
  Mg  Mg6  1  0.500  0.500  0.500  1.0
  Mg  Mg7  1  0.500  0.000  0.000  1.0
  Mg  Mg8  1  0.000  0.000  0.500  1.0
  Mg  Mg9  1  0.500  0.500  0.000  1.0
  Mg  Mg10  1  0.000  0.500  0.500  1.0
  Mg  Mg11  1  0.000  0.500  0.000  1.0
  Mg  Mg12  1  0.500  0.000  0.500  1.0
  Mg  Mg13  1  0.378  0.378  0.378  1.0
  Mg  Mg14  1  0.622  0.622  0.133  1.0
  Mg  Mg15  1  0.133  0.622  0.622  1.0
  Mg  Mg16  1  0.622  0.133  0.622  1.0
  Mg  Mg17  1  0.867  0.378  0.378  1.0
  Mg  Mg18  1  0.378  0.867  0.378  1.0
  Mg  Mg19  1  0.378  0.378  0.867  1.0
  Mg  Mg20  1  0.622  0.622  0.622  1.0
  Mg  Mg21  1  0.175  0.175  0.175  1.0
  Mg  Mg22  1  0.825  0.825  0.524  1.0
  Mg  Mg23  1  0.524  0.825  0.825  1.0
  Mg  Mg24  1  0.825  0.524  0.825  1.0
  Mg  Mg25  1  0.476  0.175  0.175  1.0
  Mg  Mg26  1  0.175  0.476  0.175  1.0
  Mg  Mg27  1  0.175  0.175  0.476  1.0
  Mg  Mg28  1  0.825  0.825  0.825  1.0
[/CIF]
.
The structure described by Mg23Sr6 crystallizes in the cubic Fm-3m space group. Sr(1) is bonded in a 12-coordinate geometry to four equivalent Mg(2), four equivalent Mg(3), and four equivalent Mg(4) atoms. There are four inequivalent Mg sites. In the first Mg site, Mg(4) is bonded in a distorted q6 geometry to three equivalent Sr(1), three equivalent Mg(2), three equivalent Mg(3), and three equivalent Mg(4) atoms. In the second Mg site, Mg(1) is bonded in a body-centered cubic geometry to eight equivalent Mg(3) atoms. In the third Mg site, Mg(2) is bonded to four equivalent Sr(1), four equivalent Mg(3), and four equivalent Mg(4) atoms to form a mixture of corner and face-sharing MgSr4Mg8 cuboctahedra. In the fourth Mg site, Mg(3) is bonded in a 10-coordinate geometry to three equivalent Sr(1), one Mg(1), three equivalent Mg(2), and three equivalent Mg(4) atoms. is represented by the CIF card [CIF]
data_Sr6Mg23
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.509
_cell_length_b   10.509
_cell_length_c   10.509
_cell_angle_alpha   60.000
_cell_angle_beta   60.000
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   820.691
_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
  Sr  Sr0  1  0.793  0.207  0.207  1.0
  Sr  Sr1  1  0.793  0.793  0.207  1.0
  Sr  Sr2  1  0.207  0.207  0.793  1.0
  Sr  Sr3  1  0.793  0.207  0.793  1.0
  Sr  Sr4  1  0.207  0.793  0.207  1.0
  Sr  Sr5  1  0.207  0.793  0.793  1.0
  Mg  Mg6  1  0.500  0.500  0.500  1.0
  Mg  Mg7  1  0.500  0.000  0.000  1.0
  Mg  Mg8  1  0.000  0.000  0.500  1.0
  Mg  Mg9  1  0.500  0.500  0.000  1.0
  Mg  Mg10  1  0.000  0.500  0.500  1.0
  Mg  Mg11  1  0.000  0.500  0.000  1.0
  Mg  Mg12  1  0.500  0.000  0.500  1.0
  Mg  Mg13  1  0.378  0.378  0.378  1.0
  Mg  Mg14  1  0.622  0.622  0.133  1.0
  Mg  Mg15  1  0.133  0.622  0.622  1.0
  Mg  Mg16  1  0.622  0.133  0.622  1.0
  Mg  Mg17  1  0.867  0.378  0.378  1.0
  Mg  Mg18  1  0.378  0.867  0.378  1.0
  Mg  Mg19  1  0.378  0.378  0.867  1.0
  Mg  Mg20  1  0.622  0.622  0.622  1.0
  Mg  Mg21  1  0.175  0.175  0.175  1.0
  Mg  Mg22  1  0.825  0.825  0.524  1.0
  Mg  Mg23  1  0.524  0.825  0.825  1.0
  Mg  Mg24  1  0.825  0.524  0.825  1.0
  Mg  Mg25  1  0.476  0.175  0.175  1.0
  Mg  Mg26  1  0.175  0.476  0.175  1.0
  Mg  Mg27  1  0.175  0.175  0.476  1.0
  Mg  Mg28  1  0.825  0.825  0.825  1.0
[/CIF]
.