The structure described by SrMg5 is Bergman Structure: Mg32(Al,Zn)49 Bergman-derived structured and crystallizes in the monoclinic Cm space group. Sr(1) is bonded to two equivalent Sr(1), one Mg(4), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(2) atoms to form SrSr2Mg10 cuboctahedra that share corners with six equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with three equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(4)SrMg11 cuboctahedra, faces with two equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with three equivalent Mg(3)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(4)SrMg11 cuboctahedra. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and three equivalent Mg(5) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to three equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Sr(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(4) atoms to form MgSr2Mg10 cuboctahedra that share corners with six equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with two equivalent Mg(4)SrMg11 cuboctahedra, edges with three equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(3)Sr2Mg10 cuboctahedra, faces with three equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with five equivalent Mg(4)SrMg11 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to one Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Mg(3) atoms to form MgSrMg11 cuboctahedra that share corners with six equivalent Mg(4)SrMg11 cuboctahedra, edges with two equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with four equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(4)SrMg11 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with five equivalent Mg(3)Sr2Mg10 cuboctahedra. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.283
_cell_length_b   6.527
_cell_length_c   8.366
_cell_angle_alpha   106.583
_cell_angle_beta   90.000
_cell_angle_gamma   104.563
_symmetry_Int_Tables_number   1
_cell_volume   165.768
_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  0.990  0.980  0.013  1.0
  Mg  Mg1  1  0.341  0.682  0.654  1.0
  Mg  Mg2  1  0.938  0.875  0.370  1.0
  Mg  Mg3  1  0.666  0.332  0.324  1.0
  Mg  Mg4  1  0.282  0.565  0.078  1.0
  Sr  Sr5  1  0.616  0.232  0.727  1.0
[/CIF]
.
The structure described by SrMg5 is Bergman Structure: Mg32(Al,Zn)49 Bergman-derived structured and crystallizes in the monoclinic Cm space group. Sr(1) is bonded to two equivalent Sr(1), one Mg(4), two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(2) atoms to form SrSr2Mg10 cuboctahedra that share corners with six equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with three equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(4)SrMg11 cuboctahedra, faces with two equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with three equivalent Mg(3)Sr2Mg10 cuboctahedra, and faces with four equivalent Mg(4)SrMg11 cuboctahedra. There are five inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and three equivalent Mg(5) atoms. In the second Mg site, Mg(2) is bonded in a 11-coordinate geometry to three equivalent Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Sr(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(5), and three equivalent Mg(4) atoms to form MgSr2Mg10 cuboctahedra that share corners with six equivalent Sr(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with two equivalent Mg(4)SrMg11 cuboctahedra, edges with three equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(3)Sr2Mg10 cuboctahedra, faces with three equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with five equivalent Mg(4)SrMg11 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to one Sr(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Mg(3) atoms to form MgSrMg11 cuboctahedra that share corners with six equivalent Mg(4)SrMg11 cuboctahedra, edges with two equivalent Mg(3)Sr2Mg10 cuboctahedra, edges with four equivalent Sr(1)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(4)SrMg11 cuboctahedra, faces with four equivalent Sr(1)Sr2Mg10 cuboctahedra, and faces with five equivalent Mg(3)Sr2Mg10 cuboctahedra. In the fifth Mg site, Mg(5) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(5), and three equivalent Mg(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.283
_cell_length_b   6.527
_cell_length_c   8.366
_cell_angle_alpha   106.583
_cell_angle_beta   90.000
_cell_angle_gamma   104.563
_symmetry_Int_Tables_number   1
_cell_volume   165.768
_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  0.990  0.980  0.013  1.0
  Mg  Mg1  1  0.341  0.682  0.654  1.0
  Mg  Mg2  1  0.938  0.875  0.370  1.0
  Mg  Mg3  1  0.666  0.332  0.324  1.0
  Mg  Mg4  1  0.282  0.565  0.078  1.0
  Sr  Sr5  1  0.616  0.232  0.727  1.0
[/CIF]
.