The compound described by Ta7Fe6 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 to six equivalent Ta(3) and six equivalent Fe(1) atoms to form distorted TaTa6Fe6 cuboctahedra that share corners with twelve equivalent Fe(1)Ta8Fe4 cuboctahedra, edges with six equivalent Ta(1)Ta6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(1)Ta8Fe4 cuboctahedra. In the second Ta site, Ta(2) is bonded in a 15-coordinate geometry to three equivalent Ta(2), six equivalent Ta(4), and six equivalent Fe(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 Fe(1) atoms. In the fourth Ta site, Ta(4) is bonded in a 14-coordinate geometry to one Ta(3), one Ta(4), six equivalent Ta(2), and six equivalent Fe(1) atoms. Fe(1) is bonded to one Ta(1), two equivalent Ta(2), two equivalent Ta(4), three equivalent Ta(3), and four equivalent Fe(1) atoms to form distorted FeTa8Fe4 cuboctahedra that share corners with two equivalent Ta(1)Ta6Fe6 cuboctahedra, corners with thirteen equivalent Fe(1)Ta8Fe4 cuboctahedra, edges with five equivalent Fe(1)Ta8Fe4 cuboctahedra, faces with three equivalent Ta(1)Ta6Fe6 cuboctahedra, and faces with ten equivalent Fe(1)Ta8Fe4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta7Fe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.939
_cell_length_b   4.939
_cell_length_c   9.458
_cell_angle_alpha   74.865
_cell_angle_beta   74.865
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   190.481
_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  0.833  0.833  0.501  1.0
  Ta  Ta2  1  0.167  0.167  0.499  1.0
  Ta  Ta3  1  0.652  0.652  0.043  1.0
  Ta  Ta4  1  0.348  0.348  0.957  1.0
  Ta  Ta5  1  0.549  0.549  0.353  1.0
  Ta  Ta6  1  0.451  0.451  0.647  1.0
  Fe  Fe7  1  0.908  0.908  0.766  1.0
  Fe  Fe8  1  0.418  0.908  0.766  1.0
  Fe  Fe9  1  0.908  0.418  0.766  1.0
  Fe  Fe10  1  0.092  0.092  0.234  1.0
  Fe  Fe11  1  0.582  0.092  0.234  1.0
  Fe  Fe12  1  0.092  0.582  0.234  1.0
[/CIF]
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The compound described by Ta7Fe6 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 to six equivalent Ta(3) and six equivalent Fe(1) atoms to form distorted TaTa6Fe6 cuboctahedra that share corners with twelve equivalent Fe(1)Ta8Fe4 cuboctahedra, edges with six equivalent Ta(1)Ta6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(1)Ta8Fe4 cuboctahedra. In the second Ta site, Ta(2) is bonded in a 15-coordinate geometry to three equivalent Ta(2), six equivalent Ta(4), and six equivalent Fe(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 Fe(1) atoms. In the fourth Ta site, Ta(4) is bonded in a 14-coordinate geometry to one Ta(3), one Ta(4), six equivalent Ta(2), and six equivalent Fe(1) atoms. Fe(1) is bonded to one Ta(1), two equivalent Ta(2), two equivalent Ta(4), three equivalent Ta(3), and four equivalent Fe(1) atoms to form distorted FeTa8Fe4 cuboctahedra that share corners with two equivalent Ta(1)Ta6Fe6 cuboctahedra, corners with thirteen equivalent Fe(1)Ta8Fe4 cuboctahedra, edges with five equivalent Fe(1)Ta8Fe4 cuboctahedra, faces with three equivalent Ta(1)Ta6Fe6 cuboctahedra, and faces with ten equivalent Fe(1)Ta8Fe4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta7Fe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.939
_cell_length_b   4.939
_cell_length_c   9.458
_cell_angle_alpha   74.865
_cell_angle_beta   74.865
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   190.481
_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  0.833  0.833  0.501  1.0
  Ta  Ta2  1  0.167  0.167  0.499  1.0
  Ta  Ta3  1  0.652  0.652  0.043  1.0
  Ta  Ta4  1  0.348  0.348  0.957  1.0
  Ta  Ta5  1  0.549  0.549  0.353  1.0
  Ta  Ta6  1  0.451  0.451  0.647  1.0
  Fe  Fe7  1  0.908  0.908  0.766  1.0
  Fe  Fe8  1  0.418  0.908  0.766  1.0
  Fe  Fe9  1  0.908  0.418  0.766  1.0
  Fe  Fe10  1  0.092  0.092  0.234  1.0
  Fe  Fe11  1  0.582  0.092  0.234  1.0
  Fe  Fe12  1  0.092  0.582  0.234  1.0
[/CIF]
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