The structure described by Mg6CoSi crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Co(1), and two equivalent Si(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 six equivalent Mg(2)Mg10Co2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, and faces with two equivalent Mg(4)Mg10Si2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Co(1), and one Si(1) atom. 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 Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, and faces with two equivalent Mg(4)Mg10Si2 cuboctahedra. Co(1) is bonded in a 12-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Mg6CoSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.590
_cell_length_b   6.096
_cell_length_c   6.096
_cell_angle_alpha   118.866
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.378
_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  0.190  0.810  1.0
  Mg  Mg1  1  0.000  0.644  0.832  1.0
  Mg  Mg2  1  0.000  0.168  0.356  1.0
  Mg  Mg3  1  0.000  0.663  0.337  1.0
  Mg  Mg4  1  0.500  0.860  0.674  1.0
  Mg  Mg5  1  0.500  0.326  0.140  1.0
  Mg  Mg6  1  0.500  0.835  0.165  1.0
  Si  Si7  1  0.500  0.315  0.685  1.0
[/CIF]
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The structure described by Mg6CoSi crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Co(1), and two equivalent Si(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 six equivalent Mg(2)Mg10Co2 cuboctahedra, edges with four equivalent Mg(4)Mg10Si2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, and faces with two equivalent Mg(4)Mg10Si2 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 3-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Co(1), and one Si(1) atom. 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 Si(1) atoms to form distorted MgMg10Si2 cuboctahedra that share corners with six equivalent Mg(4)Mg10Si2 cuboctahedra, edges with four equivalent Mg(2)Mg10Co2 cuboctahedra, faces with two equivalent Mg(2)Mg10Co2 cuboctahedra, and faces with two equivalent Mg(4)Mg10Si2 cuboctahedra. Co(1) is bonded in a 12-coordinate geometry to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Si(1) atoms. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. is represented by the CIF file [CIF]
data_Mg6CoSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.590
_cell_length_b   6.096
_cell_length_c   6.096
_cell_angle_alpha   118.866
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.378
_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  0.190  0.810  1.0
  Mg  Mg1  1  0.000  0.644  0.832  1.0
  Mg  Mg2  1  0.000  0.168  0.356  1.0
  Mg  Mg3  1  0.000  0.663  0.337  1.0
  Mg  Mg4  1  0.500  0.860  0.674  1.0
  Mg  Mg5  1  0.500  0.326  0.140  1.0
  Mg  Mg6  1  0.500  0.835  0.165  1.0
  Si  Si7  1  0.500  0.315  0.685  1.0
[/CIF]
.