The material structure described by SrMg3 crystallizes in the orthorhombic Pmm2 space group. Sr(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrSr2Mg10 cuboctahedra that share corners with eight equivalent Mg(1)Sr4Mg8 cuboctahedra, corners with ten equivalent Sr(1)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(1)Sr4Mg8 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr4Mg8 cuboctahedra. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), and four equivalent Mg(3) atoms to form distorted MgSr4Mg8 cuboctahedra that share corners with eight equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Sr4Mg8 cuboctahedra, edges with two equivalent Mg(1)Sr4Mg8 cuboctahedra, edges with four equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to four equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), and two equivalent Mg(3) 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(3), and four equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.482
_cell_length_b   5.445
_cell_length_c   6.303
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   119.503
_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  0.500  0.000  0.162  1.0
  Mg  Mg1  1  0.000  0.000  0.656  1.0
  Mg  Mg2  1  0.000  0.500  0.373  1.0
  Mg  Mg3  1  0.500  0.500  0.809  1.0
[/CIF]
.
The material structure described by SrMg3 crystallizes in the orthorhombic Pmm2 space group. Sr(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrSr2Mg10 cuboctahedra that share corners with eight equivalent Mg(1)Sr4Mg8 cuboctahedra, corners with ten equivalent Sr(1)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(1)Sr4Mg8 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr4Mg8 cuboctahedra. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to four equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), and four equivalent Mg(3) atoms to form distorted MgSr4Mg8 cuboctahedra that share corners with eight equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Sr4Mg8 cuboctahedra, edges with two equivalent Mg(1)Sr4Mg8 cuboctahedra, edges with four equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Sr4Mg8 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to four equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), and two equivalent Mg(3) 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(3), and four equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.482
_cell_length_b   5.445
_cell_length_c   6.303
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   119.503
_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  0.500  0.000  0.162  1.0
  Mg  Mg1  1  0.000  0.000  0.656  1.0
  Mg  Mg2  1  0.000  0.500  0.373  1.0
  Mg  Mg3  1  0.500  0.500  0.809  1.0
[/CIF]
.