The crystal structure described by Mg6HfCo crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Hf(1), and two equivalent Co(1) atoms to form distorted MgHf2Mg8Co2 cuboctahedra that share corners with four equivalent Co(1)Hf2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with two equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Hf2Mg10 cuboctahedra, edges with four equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Co(1)Hf2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Co(1) atoms. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Hf2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, and faces with six equivalent Co(1)Hf2Mg10 cuboctahedra. Hf(1) is bonded in a distorted linear geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. Co(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form distorted CoHf2Mg10 cuboctahedra that share corners with six equivalent Co(1)Hf2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, faces with two equivalent Co(1)Hf2Mg10 cuboctahedra, faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, and faces with six equivalent Mg(4)Hf2Mg10 cuboctahedra. is represented by the CIF file [CIF]
data_HfMg6Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.916
_cell_length_b   5.764
_cell_length_c   6.318
_cell_angle_alpha   117.140
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   159.303
_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  0.166  0.332  1.0
  Hf  Hf1  1  0.000  0.680  0.359  1.0
  Mg  Mg2  1  1.000  0.679  0.856  1.0
  Mg  Mg3  1  1.000  0.176  0.856  1.0
  Mg  Mg4  1  0.500  0.835  0.162  1.0
  Mg  Mg5  1  0.500  0.328  0.162  1.0
  Mg  Mg6  1  0.500  0.306  0.612  1.0
  Mg  Mg7  1  0.500  0.830  0.661  1.0
[/CIF]
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The crystal structure described by Mg6HfCo crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Hf(1), and two equivalent Co(1) atoms to form distorted MgHf2Mg8Co2 cuboctahedra that share corners with four equivalent Co(1)Hf2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with two equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with two equivalent Co(1)Hf2Mg10 cuboctahedra, edges with four equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with two equivalent Co(1)Hf2Mg10 cuboctahedra, and faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 2-coordinate geometry to two equivalent Mg(1), two equivalent Mg(4), and two equivalent Co(1) atoms. In the third Mg site, Mg(3) is bonded in a 2-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form MgHf2Mg10 cuboctahedra that share corners with six equivalent Mg(4)Hf2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, faces with two equivalent Mg(4)Hf2Mg10 cuboctahedra, faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, and faces with six equivalent Co(1)Hf2Mg10 cuboctahedra. Hf(1) is bonded in a distorted linear geometry to two equivalent Mg(4), four equivalent Mg(1), and two equivalent Co(1) atoms. Co(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Hf(1) atoms to form distorted CoHf2Mg10 cuboctahedra that share corners with six equivalent Co(1)Hf2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, edges with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, faces with two equivalent Co(1)Hf2Mg10 cuboctahedra, faces with four equivalent Mg(1)Hf2Mg8Co2 cuboctahedra, and faces with six equivalent Mg(4)Hf2Mg10 cuboctahedra. is represented by the CIF file [CIF]
data_HfMg6Co
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.916
_cell_length_b   5.764
_cell_length_c   6.318
_cell_angle_alpha   117.140
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   159.303
_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  0.166  0.332  1.0
  Hf  Hf1  1  0.000  0.680  0.359  1.0
  Mg  Mg2  1  1.000  0.679  0.856  1.0
  Mg  Mg3  1  1.000  0.176  0.856  1.0
  Mg  Mg4  1  0.500  0.835  0.162  1.0
  Mg  Mg5  1  0.500  0.328  0.162  1.0
  Mg  Mg6  1  0.500  0.306  0.612  1.0
  Mg  Mg7  1  0.500  0.830  0.661  1.0
[/CIF]
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