The material described by Sr3Mg crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to six equivalent Sr(1) and six equivalent Sr(2) atoms to form a mixture of edge, corner, and face-sharing SrSr12 cuboctahedra. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to three equivalent Sr(1) and three equivalent Mg(1) atoms. Mg(1) is bonded in a 6-coordinate geometry to six equivalent Sr(2) atoms. is represented by the CIF card [CIF]
data_Sr3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.208
_cell_length_b   4.208
_cell_length_c   12.373
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   189.730
_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  0.667  0.333  0.000  1.0
  Sr  Sr1  1  0.000  0.000  0.285  1.0
  Sr  Sr2  1  0.000  0.000  0.715  1.0
  Mg  Mg3  1  0.667  0.333  0.500  1.0
[/CIF]
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The material described by Sr3Mg crystallizes in the hexagonal P-6m2 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to six equivalent Sr(1) and six equivalent Sr(2) atoms to form a mixture of edge, corner, and face-sharing SrSr12 cuboctahedra. In the second Sr site, Sr(2) is bonded in a 3-coordinate geometry to three equivalent Sr(1) and three equivalent Mg(1) atoms. Mg(1) is bonded in a 6-coordinate geometry to six equivalent Sr(2) atoms. is represented by the CIF card [CIF]
data_Sr3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.208
_cell_length_b   4.208
_cell_length_c   12.373
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   189.730
_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  0.667  0.333  0.000  1.0
  Sr  Sr1  1  0.000  0.000  0.285  1.0
  Sr  Sr2  1  0.000  0.000  0.715  1.0
  Mg  Mg3  1  0.667  0.333  0.500  1.0
[/CIF]
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