The structure described by SrMg5 crystallizes in the trigonal R32 space group. Sr(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form SrMg12 cuboctahedra that share corners with six equivalent Sr(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with six equivalent Sr(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra, faces with eight equivalent Mg(2)Sr3Mg9 cuboctahedra, and faces with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), four equivalent Mg(2), and six equivalent Mg(1) atoms to form distorted MgSr2Mg10 cuboctahedra that share corners with eighteen equivalent Mg(1)Sr2Mg10 cuboctahedra, edges with four equivalent Sr(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Sr2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Sr3Mg9 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, faces with eight equivalent Mg(1)Sr2Mg10 cuboctahedra, and faces with eight equivalent Mg(2)Sr3Mg9 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Sr(1), three equivalent Mg(2), and six equivalent Mg(1) atoms to form distorted MgSr3Mg9 cuboctahedra that share corners with six equivalent Sr(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with six equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Sr3Mg9 cuboctahedra, and faces with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_SrMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.656
_cell_length_b   6.656
_cell_length_c   6.656
_cell_angle_alpha   51.572
_cell_angle_beta   51.572
_cell_angle_gamma   51.572
_symmetry_Int_Tables_number   1
_cell_volume   167.119
_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  0.500  0.500  1.0
  Mg  Mg1  1  0.000  0.673  0.327  1.0
  Mg  Mg2  1  0.834  0.834  0.834  1.0
  Mg  Mg3  1  0.673  0.327  0.000  1.0
  Mg  Mg4  1  0.327  0.000  0.673  1.0
  Mg  Mg5  1  0.166  0.166  0.166  1.0
[/CIF]
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The structure described by SrMg5 crystallizes in the trigonal R32 space group. Sr(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form SrMg12 cuboctahedra that share corners with six equivalent Sr(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with six equivalent Sr(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra, faces with eight equivalent Mg(2)Sr3Mg9 cuboctahedra, and faces with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Sr(1), four equivalent Mg(2), and six equivalent Mg(1) atoms to form distorted MgSr2Mg10 cuboctahedra that share corners with eighteen equivalent Mg(1)Sr2Mg10 cuboctahedra, edges with four equivalent Sr(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Sr2Mg10 cuboctahedra, edges with eight equivalent Mg(2)Sr3Mg9 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, faces with eight equivalent Mg(1)Sr2Mg10 cuboctahedra, and faces with eight equivalent Mg(2)Sr3Mg9 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Sr(1), three equivalent Mg(2), and six equivalent Mg(1) atoms to form distorted MgSr3Mg9 cuboctahedra that share corners with six equivalent Sr(1)Mg12 cuboctahedra, corners with twelve equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with six equivalent Mg(2)Sr3Mg9 cuboctahedra, edges with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra, faces with four equivalent Sr(1)Mg12 cuboctahedra, faces with four equivalent Mg(2)Sr3Mg9 cuboctahedra, and faces with twelve equivalent Mg(1)Sr2Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_SrMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.656
_cell_length_b   6.656
_cell_length_c   6.656
_cell_angle_alpha   51.572
_cell_angle_beta   51.572
_cell_angle_gamma   51.572
_symmetry_Int_Tables_number   1
_cell_volume   167.119
_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  0.500  0.500  1.0
  Mg  Mg1  1  0.000  0.673  0.327  1.0
  Mg  Mg2  1  0.834  0.834  0.834  1.0
  Mg  Mg3  1  0.673  0.327  0.000  1.0
  Mg  Mg4  1  0.327  0.000  0.673  1.0
  Mg  Mg5  1  0.166  0.166  0.166  1.0
[/CIF]
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