The structure described by Sr5Mg is beta-derived structured and crystallizes in the trigonal R32 space group. There are five inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1,1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the second Sr site, Sr(2) is bonded to three equivalent Sr(2); six Sr(1,1,1); and three equivalent Mg(1) atoms to form distorted SrSr9Mg3 cuboctahedra that share corners with six equivalent Mg(1)Sr12 cuboctahedra; corners with twelve equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with six equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra; faces with four equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; and faces with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra. In the third Sr site, Sr(1) is bonded to four equivalent Sr(2), six equivalent Sr(1), and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the fourth Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1,1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the fifth Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. Mg(1) is bonded to six Sr(1,1,1) and six equivalent Sr(2) atoms to form distorted MgSr12 cuboctahedra that share corners with six equivalent Mg(1)Sr12 cuboctahedra; corners with twelve equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with six equivalent Mg(1)Sr12 cuboctahedra; edges with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra; faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; and faces with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Sr5Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.959
_cell_length_b   7.959
_cell_length_c   7.959
_cell_angle_alpha   52.928
_cell_angle_beta   52.928
_cell_angle_gamma   52.928
_symmetry_Int_Tables_number   1
_cell_volume   297.451
_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  0.000  0.662  0.338  1.0
  Sr  Sr1  1  0.834  0.834  0.834  1.0
  Sr  Sr2  1  0.662  0.338  0.000  1.0
  Sr  Sr3  1  0.338  0.000  0.662  1.0
  Sr  Sr4  1  0.166  0.166  0.166  1.0
  Mg  Mg5  1  0.500  0.500  0.500  1.0
[/CIF]
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The structure described by Sr5Mg is beta-derived structured and crystallizes in the trigonal R32 space group. There are five inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1,1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the second Sr site, Sr(2) is bonded to three equivalent Sr(2); six Sr(1,1,1); and three equivalent Mg(1) atoms to form distorted SrSr9Mg3 cuboctahedra that share corners with six equivalent Mg(1)Sr12 cuboctahedra; corners with twelve equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with six equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra; faces with four equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; and faces with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra. In the third Sr site, Sr(1) is bonded to four equivalent Sr(2), six equivalent Sr(1), and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the fourth Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1,1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. In the fifth Sr site, Sr(1) is bonded to four equivalent Sr(2); six Sr(1,1); and two equivalent Mg(1) atoms to form distorted SrSr10Mg2 cuboctahedra that share corners with eighteen Sr(1,1)Sr10Mg2 cuboctahedra; edges with four equivalent Mg(1)Sr12 cuboctahedra; edges with six equivalent Sr(1)Sr10Mg2 cuboctahedra; edges with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; faces with four equivalent Mg(1)Sr12 cuboctahedra; faces with eight Sr(1,1,1)Sr10Mg2 cuboctahedra; and faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra. Mg(1) is bonded to six Sr(1,1,1) and six equivalent Sr(2) atoms to form distorted MgSr12 cuboctahedra that share corners with six equivalent Mg(1)Sr12 cuboctahedra; corners with twelve equivalent Sr(2)Sr9Mg3 cuboctahedra; edges with six equivalent Mg(1)Sr12 cuboctahedra; edges with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra; faces with eight equivalent Sr(2)Sr9Mg3 cuboctahedra; and faces with twelve Sr(1,1,1)Sr10Mg2 cuboctahedra. is represented by the CIF file [CIF]
data_Sr5Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.959
_cell_length_b   7.959
_cell_length_c   7.959
_cell_angle_alpha   52.928
_cell_angle_beta   52.928
_cell_angle_gamma   52.928
_symmetry_Int_Tables_number   1
_cell_volume   297.451
_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  0.000  0.662  0.338  1.0
  Sr  Sr1  1  0.834  0.834  0.834  1.0
  Sr  Sr2  1  0.662  0.338  0.000  1.0
  Sr  Sr3  1  0.338  0.000  0.662  1.0
  Sr  Sr4  1  0.166  0.166  0.166  1.0
  Mg  Mg5  1  0.500  0.500  0.500  1.0
[/CIF]
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