The crystal structure described by SrMg6Nb crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Nb(1) atoms to form SrMg10Nb2 cuboctahedra that share corners with four equivalent Mg(2)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Mg10Nb2 cuboctahedra, edges with two equivalent Mg(2)Sr2Mg10 cuboctahedra, edges with four equivalent Nb(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg10Nb2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Mg10Nb2 cuboctahedra, corners with six equivalent Mg(2)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Mg10Nb2 cuboctahedra, edges with four equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, and faces with six equivalent Nb(1)Sr2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Nb(1) atoms to form MgMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Nb2 cuboctahedra, edges with two equivalent Nb(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Sr(1)Mg10Nb2 cuboctahedra. Nb(1) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form NbSr2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra, corners with six equivalent Nb(1)Sr2Mg10 cuboctahedra, edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra, edges with four equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Mg(2)Sr2Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_SrMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   6.582
_cell_length_c   6.582
_cell_angle_alpha   118.844
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   196.850
_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  1.000  0.636  0.816  1.0
  Mg  Mg1  1  0.000  0.184  0.364  1.0
  Mg  Mg2  1  0.000  0.670  0.330  1.0
  Mg  Mg3  1  0.500  0.812  0.650  1.0
  Mg  Mg4  1  0.500  0.350  0.188  1.0
  Mg  Mg5  1  0.500  0.842  0.158  1.0
  Nb  Nb6  1  0.500  0.349  0.651  1.0
  Sr  Sr7  1  0.000  0.158  0.842  1.0
[/CIF]
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The crystal structure described by SrMg6Nb crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Nb(1) atoms to form SrMg10Nb2 cuboctahedra that share corners with four equivalent Mg(2)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Mg10Nb2 cuboctahedra, edges with two equivalent Mg(2)Sr2Mg10 cuboctahedra, edges with four equivalent Nb(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg10Nb2 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Mg10Nb2 cuboctahedra, corners with six equivalent Mg(2)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Mg10Nb2 cuboctahedra, edges with four equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, and faces with six equivalent Nb(1)Sr2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Nb(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Nb(1) atoms to form MgMg10Nb2 cuboctahedra that share corners with four equivalent Nb(1)Sr2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Nb2 cuboctahedra, edges with two equivalent Nb(1)Sr2Mg10 cuboctahedra, edges with four equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(2)Sr2Mg10 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Sr(1)Mg10Nb2 cuboctahedra. Nb(1) is bonded to two equivalent Sr(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form NbSr2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Nb2 cuboctahedra, corners with six equivalent Nb(1)Sr2Mg10 cuboctahedra, edges with two equivalent Mg(4)Mg10Nb2 cuboctahedra, edges with four equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Sr(1)Mg10Nb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Nb2 cuboctahedra, faces with two equivalent Nb(1)Sr2Mg10 cuboctahedra, and faces with six equivalent Mg(2)Sr2Mg10 cuboctahedra. is represented by the CIF card [CIF]
data_SrMg6Nb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   6.582
_cell_length_c   6.582
_cell_angle_alpha   118.844
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   196.850
_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  1.000  0.636  0.816  1.0
  Mg  Mg1  1  0.000  0.184  0.364  1.0
  Mg  Mg2  1  0.000  0.670  0.330  1.0
  Mg  Mg3  1  0.500  0.812  0.650  1.0
  Mg  Mg4  1  0.500  0.350  0.188  1.0
  Mg  Mg5  1  0.500  0.842  0.158  1.0
  Nb  Nb6  1  0.500  0.349  0.651  1.0
  Sr  Sr7  1  0.000  0.158  0.842  1.0
[/CIF]
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