The structure described by Mg6CoSb crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Co(1), and two equivalent Sb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Co(1)Mg10Sb2 cuboctahedra, corners with six equivalent Mg(2)Mg10Co2 cuboctahedra, edges with two equivalent Co(1)Mg10Sb2 cuboctahedra, edges with four equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, and faces with six equivalent Sb(1)Mg10Co2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Co(1), and two equivalent Sb(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 Sb(1) atoms to form distorted MgMg10Sb2 cuboctahedra that share corners with four equivalent Sb(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(4)Mg10Sb2 cuboctahedra, edges with two equivalent Sb(1)Mg10Co2 cuboctahedra, edges with four equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Co(1)Mg10Sb2 cuboctahedra. Co(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Sb(1) atoms to form CoMg10Sb2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Co2 cuboctahedra, corners with six equivalent Co(1)Mg10Sb2 cuboctahedra, edges with two equivalent Mg(2)Mg10Co2 cuboctahedra, edges with four equivalent Sb(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Sb2 cuboctahedra. Sb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form SbMg10Co2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Sb2 cuboctahedra, corners with six equivalent Sb(1)Mg10Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Sb2 cuboctahedra, edges with four equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Co2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg6CoSb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.881
_cell_length_b   6.170
_cell_length_c   6.170
_cell_angle_alpha   119.390
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   161.928
_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
  Co  Co0  1  0.000  0.158  0.842  1.0
  Mg  Mg1  1  0.000  0.679  0.838  1.0
  Mg  Mg2  1  0.000  0.162  0.321  1.0
  Mg  Mg3  1  0.000  0.666  0.334  1.0
  Mg  Mg4  1  0.500  0.853  0.675  1.0
  Mg  Mg5  1  0.500  0.325  0.147  1.0
  Mg  Mg6  1  0.500  0.831  0.169  1.0
  Sb  Sb7  1  0.500  0.327  0.673  1.0
[/CIF]
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The structure described by Mg6CoSb crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Co(1), and two equivalent Sb(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Co(1)Mg10Sb2 cuboctahedra, corners with six equivalent Mg(2)Mg10Co2 cuboctahedra, edges with two equivalent Co(1)Mg10Sb2 cuboctahedra, edges with four equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, and faces with six equivalent Sb(1)Mg10Co2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Co(1), and two equivalent Sb(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 Sb(1) atoms to form distorted MgMg10Sb2 cuboctahedra that share corners with four equivalent Sb(1)Mg10Co2 cuboctahedra, corners with six equivalent Mg(4)Mg10Sb2 cuboctahedra, edges with two equivalent Sb(1)Mg10Co2 cuboctahedra, edges with four equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Co(1)Mg10Sb2 cuboctahedra. Co(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Sb(1) atoms to form CoMg10Sb2 cuboctahedra that share corners with four equivalent Mg(2)Mg10Co2 cuboctahedra, corners with six equivalent Co(1)Mg10Sb2 cuboctahedra, edges with two equivalent Mg(2)Mg10Co2 cuboctahedra, edges with four equivalent Sb(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Sb2 cuboctahedra. Sb(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Co(1) atoms to form SbMg10Co2 cuboctahedra that share corners with four equivalent Mg(4)Mg10Sb2 cuboctahedra, corners with six equivalent Sb(1)Mg10Co2 cuboctahedra, edges with two equivalent Mg(4)Mg10Sb2 cuboctahedra, edges with four equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Mg(4)Mg10Sb2 cuboctahedra, faces with two equivalent Co(1)Mg10Sb2 cuboctahedra, faces with two equivalent Sb(1)Mg10Co2 cuboctahedra, and faces with six equivalent Mg(2)Mg10Co2 cuboctahedra. is represented by the CIF file [CIF]
data_Mg6CoSb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.881
_cell_length_b   6.170
_cell_length_c   6.170
_cell_angle_alpha   119.390
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   161.928
_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
  Co  Co0  1  0.000  0.158  0.842  1.0
  Mg  Mg1  1  0.000  0.679  0.838  1.0
  Mg  Mg2  1  0.000  0.162  0.321  1.0
  Mg  Mg3  1  0.000  0.666  0.334  1.0
  Mg  Mg4  1  0.500  0.853  0.675  1.0
  Mg  Mg5  1  0.500  0.325  0.147  1.0
  Mg  Mg6  1  0.500  0.831  0.169  1.0
  Sb  Sb7  1  0.500  0.327  0.673  1.0
[/CIF]
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