The material described by Co6Ta7 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the trigonal R-3m space group. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ta(3) and six equivalent Co(1) atoms. In the second Ta site, Ta(2) is bonded in a 6-coordinate geometry to six equivalent Co(1) atoms. In the third Ta site, Ta(3) is bonded in a 16-coordinate geometry to one Ta(4), three equivalent Ta(1), three equivalent Ta(3), and nine equivalent Co(1) atoms. In the fourth Ta site, Ta(4) is bonded in a 8-coordinate geometry to one Ta(3), one Ta(4), and six equivalent Co(1) atoms. Co(1) is bonded to one Ta(1), two equivalent Ta(2), two equivalent Ta(4), three equivalent Ta(3), and four equivalent Co(1) atoms to form a mixture of distorted corner, edge, and face-sharing CoTa8Co4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta7Co6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.952
_cell_length_b   4.952
_cell_length_c   9.181
_cell_angle_alpha   74.355
_cell_angle_beta   74.355
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   185.304
_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
  Ta  Ta0  1  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.167  0.167  0.499  1.0
  Ta  Ta2  1  0.833  0.833  0.501  1.0
  Ta  Ta3  1  0.346  0.346  0.963  1.0
  Ta  Ta4  1  0.654  0.654  0.037  1.0
  Ta  Ta5  1  0.451  0.451  0.647  1.0
  Ta  Ta6  1  0.549  0.549  0.353  1.0
  Co  Co7  1  0.581  0.093  0.233  1.0
  Co  Co8  1  0.093  0.093  0.233  1.0
  Co  Co9  1  0.093  0.581  0.233  1.0
  Co  Co10  1  0.419  0.907  0.767  1.0
  Co  Co11  1  0.907  0.907  0.767  1.0
  Co  Co12  1  0.907  0.419  0.767  1.0
[/CIF]
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The material described by Co6Ta7 is Frank-Kasper $\mu$ Phase-like structured and crystallizes in the trigonal R-3m space group. There are four inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a distorted hexagonal planar geometry to six equivalent Ta(3) and six equivalent Co(1) atoms. In the second Ta site, Ta(2) is bonded in a 6-coordinate geometry to six equivalent Co(1) atoms. In the third Ta site, Ta(3) is bonded in a 16-coordinate geometry to one Ta(4), three equivalent Ta(1), three equivalent Ta(3), and nine equivalent Co(1) atoms. In the fourth Ta site, Ta(4) is bonded in a 8-coordinate geometry to one Ta(3), one Ta(4), and six equivalent Co(1) atoms. Co(1) is bonded to one Ta(1), two equivalent Ta(2), two equivalent Ta(4), three equivalent Ta(3), and four equivalent Co(1) atoms to form a mixture of distorted corner, edge, and face-sharing CoTa8Co4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta7Co6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.952
_cell_length_b   4.952
_cell_length_c   9.181
_cell_angle_alpha   74.355
_cell_angle_beta   74.355
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   185.304
_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
  Ta  Ta0  1  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.167  0.167  0.499  1.0
  Ta  Ta2  1  0.833  0.833  0.501  1.0
  Ta  Ta3  1  0.346  0.346  0.963  1.0
  Ta  Ta4  1  0.654  0.654  0.037  1.0
  Ta  Ta5  1  0.451  0.451  0.647  1.0
  Ta  Ta6  1  0.549  0.549  0.353  1.0
  Co  Co7  1  0.581  0.093  0.233  1.0
  Co  Co8  1  0.093  0.093  0.233  1.0
  Co  Co9  1  0.093  0.581  0.233  1.0
  Co  Co10  1  0.419  0.907  0.767  1.0
  Co  Co11  1  0.907  0.907  0.767  1.0
  Co  Co12  1  0.907  0.419  0.767  1.0
[/CIF]
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