The material structure described by Co7Hf2 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 14-coordinate geometry to two equivalent Co(4), four equivalent Co(1), and eight equivalent Co(2) atoms. In the second Hf site, Hf(2) is bonded in a 14-coordinate geometry to two equivalent Co(4), four equivalent Co(1), and eight equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Hf(1), two equivalent Hf(2), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), and two equivalent Co(4) atoms to form a mixture of corner, edge, and face-sharing CoHf4Co8 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to four equivalent Hf(1), one Co(4), two equivalent Co(1), and five equivalent Co(2) atoms. In the third Co site, Co(3) is bonded in a 12-coordinate geometry to four equivalent Hf(2), one Co(4), two equivalent Co(1), and five equivalent Co(3) atoms. In the fourth Co site, Co(4) is bonded to two equivalent Hf(1), two equivalent Hf(2), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form a mixture of corner, edge, and face-sharing CoHf4Co8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf2Co7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.751
_cell_length_b   4.751
_cell_length_c   12.069
_cell_angle_alpha   87.851
_cell_angle_beta   87.851
_cell_angle_gamma   121.665
_symmetry_Int_Tables_number   1
_cell_volume   231.192
_cell_formula_units_Z   2
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
  Hf  Hf0  1  0.260  0.260  0.116  1.0
  Hf  Hf1  1  0.740  0.740  0.884  1.0
  Hf  Hf2  1  0.210  0.210  0.383  1.0
  Hf  Hf3  1  0.790  0.790  0.617  1.0
  Co  Co4  1  0.764  0.264  0.750  1.0
  Co  Co5  1  0.264  0.764  0.750  1.0
  Co  Co6  1  0.236  0.736  0.250  1.0
  Co  Co7  1  0.736  0.236  0.250  1.0
  Co  Co8  1  0.061  0.393  0.923  1.0
  Co  Co9  1  0.393  0.061  0.923  1.0
  Co  Co10  1  0.939  0.607  0.077  1.0
  Co  Co11  1  0.607  0.939  0.077  1.0
  Co  Co12  1  0.134  0.469  0.577  1.0
  Co  Co13  1  0.469  0.134  0.577  1.0
  Co  Co14  1  0.866  0.531  0.423  1.0
  Co  Co15  1  0.531  0.866  0.423  1.0
  Co  Co16  1  0.264  0.264  0.749  1.0
  Co  Co17  1  0.736  0.736  0.251  1.0
[/CIF]
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The material structure described by Co7Hf2 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 14-coordinate geometry to two equivalent Co(4), four equivalent Co(1), and eight equivalent Co(2) atoms. In the second Hf site, Hf(2) is bonded in a 14-coordinate geometry to two equivalent Co(4), four equivalent Co(1), and eight equivalent Co(3) atoms. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Hf(1), two equivalent Hf(2), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), and two equivalent Co(4) atoms to form a mixture of corner, edge, and face-sharing CoHf4Co8 cuboctahedra. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to four equivalent Hf(1), one Co(4), two equivalent Co(1), and five equivalent Co(2) atoms. In the third Co site, Co(3) is bonded in a 12-coordinate geometry to four equivalent Hf(2), one Co(4), two equivalent Co(1), and five equivalent Co(3) atoms. In the fourth Co site, Co(4) is bonded to two equivalent Hf(1), two equivalent Hf(2), two equivalent Co(2), two equivalent Co(3), and four equivalent Co(1) atoms to form a mixture of corner, edge, and face-sharing CoHf4Co8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Hf2Co7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.751
_cell_length_b   4.751
_cell_length_c   12.069
_cell_angle_alpha   87.851
_cell_angle_beta   87.851
_cell_angle_gamma   121.665
_symmetry_Int_Tables_number   1
_cell_volume   231.192
_cell_formula_units_Z   2
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
  Hf  Hf0  1  0.260  0.260  0.116  1.0
  Hf  Hf1  1  0.740  0.740  0.884  1.0
  Hf  Hf2  1  0.210  0.210  0.383  1.0
  Hf  Hf3  1  0.790  0.790  0.617  1.0
  Co  Co4  1  0.764  0.264  0.750  1.0
  Co  Co5  1  0.264  0.764  0.750  1.0
  Co  Co6  1  0.236  0.736  0.250  1.0
  Co  Co7  1  0.736  0.236  0.250  1.0
  Co  Co8  1  0.061  0.393  0.923  1.0
  Co  Co9  1  0.393  0.061  0.923  1.0
  Co  Co10  1  0.939  0.607  0.077  1.0
  Co  Co11  1  0.607  0.939  0.077  1.0
  Co  Co12  1  0.134  0.469  0.577  1.0
  Co  Co13  1  0.469  0.134  0.577  1.0
  Co  Co14  1  0.866  0.531  0.423  1.0
  Co  Co15  1  0.531  0.866  0.423  1.0
  Co  Co16  1  0.264  0.264  0.749  1.0
  Co  Co17  1  0.736  0.736  0.251  1.0
[/CIF]
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