The structure described by TaCuAl crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Cu(3); two equivalent Cu(1); two equivalent Cu(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the second Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the third Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the fourth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Cu(3); two equivalent Cu(1); two equivalent Cu(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the fifth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the sixth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Al(1); and four equivalent Al(2) atoms to form distorted CuTa6Al6 cuboctahedra that share corners with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Cu(1)Ta6Al6 cuboctahedra, corners with eight equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with two equivalent Cu(1)Ta6Al6 cuboctahedra, edges with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, faces with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, and faces with eight equivalent Al(2)Ta6Al4Cu2 cuboctahedra. In the second Cu site, Cu(2) is bonded to two Ta(1,1); four Ta(2,2,2,2); two equivalent Cu(2); two equivalent Cu(3); and two equivalent Al(1) atoms to form distorted CuTa6Al2Cu4 cuboctahedra that share corners with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Cu(1)Ta6Al6 cuboctahedra, corners with six equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with two equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, faces with two equivalent Cu(1)Ta6Al6 cuboctahedra, faces with two equivalent Al(2)Ta6Al4Cu2 cuboctahedra, faces with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, and faces with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra. In the third Cu site, Cu(3) is bonded to two Ta(1,1); four Ta(2,2); four equivalent Cu(2); and two equivalent Al(1) atoms to form distorted CuTa6Al2Cu4 cuboctahedra that share corners with two equivalent Cu(1)Ta6Al6 cuboctahedra, corners with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with eight equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, edges with four equivalent Cu(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, and faces with eight equivalent Cu(2)Ta6Al2Cu4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 4-coordinate geometry to three equivalent Ta(1); three Ta(2,2); one Cu(1); one Cu(3); two equivalent Cu(2); and two equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Cu(1); two equivalent Al(1); and two equivalent Al(2) atoms to form distorted AlTa6Al4Cu2 cuboctahedra that share corners with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, corners with six equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with two equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, faces with two equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, faces with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, faces with four equivalent Cu(1)Ta6Al6 cuboctahedra, and faces with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra. is represented by the CIF card [CIF]
data_TaAlCu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.947
_cell_length_b   4.947
_cell_length_c   8.029
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   61.118
_symmetry_Int_Tables_number   1
_cell_volume   172.030
_cell_formula_units_Z   4
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  0.335  0.335  0.561  1.0
  Ta  Ta1  1  0.663  0.663  0.434  1.0
  Ta  Ta2  1  0.663  0.663  0.066  1.0
  Ta  Ta3  1  0.335  0.335  0.939  1.0
  Al  Al4  1  0.995  0.995  0.487  1.0
  Al  Al5  1  0.995  0.995  0.013  1.0
  Al  Al6  1  0.835  0.351  0.750  1.0
  Al  Al7  1  0.351  0.835  0.750  1.0
  Cu  Cu8  1  0.838  0.838  0.750  1.0
  Cu  Cu9  1  0.171  0.651  0.250  1.0
  Cu  Cu10  1  0.651  0.171  0.250  1.0
  Cu  Cu11  1  0.170  0.170  0.250  1.0
[/CIF]
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The structure described by TaCuAl crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Cu(3); two equivalent Cu(1); two equivalent Cu(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the second Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the third Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the fourth Ta site, Ta(1) is bonded in a 16-coordinate geometry to one Ta(1); three Ta(2,2); one Cu(3); two equivalent Cu(1); two equivalent Cu(2); three equivalent Al(1); and four equivalent Al(2) atoms. In the fifth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. In the sixth Ta site, Ta(2) is bonded in a 16-coordinate geometry to one Ta(2), three equivalent Ta(1), one Cu(1), two equivalent Cu(3), four equivalent Cu(2), two equivalent Al(2), and three equivalent Al(1) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Al(1); and four equivalent Al(2) atoms to form distorted CuTa6Al6 cuboctahedra that share corners with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Cu(1)Ta6Al6 cuboctahedra, corners with eight equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with two equivalent Cu(1)Ta6Al6 cuboctahedra, edges with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, faces with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, and faces with eight equivalent Al(2)Ta6Al4Cu2 cuboctahedra. In the second Cu site, Cu(2) is bonded to two Ta(1,1); four Ta(2,2,2,2); two equivalent Cu(2); two equivalent Cu(3); and two equivalent Al(1) atoms to form distorted CuTa6Al2Cu4 cuboctahedra that share corners with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Cu(1)Ta6Al6 cuboctahedra, corners with six equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with two equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, faces with two equivalent Cu(1)Ta6Al6 cuboctahedra, faces with two equivalent Al(2)Ta6Al4Cu2 cuboctahedra, faces with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, and faces with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra. In the third Cu site, Cu(3) is bonded to two Ta(1,1); four Ta(2,2); four equivalent Cu(2); and two equivalent Al(1) atoms to form distorted CuTa6Al2Cu4 cuboctahedra that share corners with two equivalent Cu(1)Ta6Al6 cuboctahedra, corners with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with eight equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, edges with four equivalent Cu(1)Ta6Al6 cuboctahedra, faces with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, and faces with eight equivalent Cu(2)Ta6Al2Cu4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 4-coordinate geometry to three equivalent Ta(1); three Ta(2,2); one Cu(1); one Cu(3); two equivalent Cu(2); and two equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two Ta(2,2); four Ta(1,1); two equivalent Cu(1); two equivalent Al(1); and two equivalent Al(2) atoms to form distorted AlTa6Al4Cu2 cuboctahedra that share corners with four equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, corners with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra, corners with six equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, edges with two equivalent Al(2)Ta6Al4Cu2 cuboctahedra, edges with four equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, faces with two equivalent Cu(2)Ta6Al2Cu4 cuboctahedra, faces with two equivalent Cu(3)Ta6Al2Cu4 cuboctahedra, faces with four equivalent Cu(1)Ta6Al6 cuboctahedra, and faces with four equivalent Al(2)Ta6Al4Cu2 cuboctahedra. is represented by the CIF card [CIF]
data_TaAlCu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.947
_cell_length_b   4.947
_cell_length_c   8.029
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   61.118
_symmetry_Int_Tables_number   1
_cell_volume   172.030
_cell_formula_units_Z   4
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  0.335  0.335  0.561  1.0
  Ta  Ta1  1  0.663  0.663  0.434  1.0
  Ta  Ta2  1  0.663  0.663  0.066  1.0
  Ta  Ta3  1  0.335  0.335  0.939  1.0
  Al  Al4  1  0.995  0.995  0.487  1.0
  Al  Al5  1  0.995  0.995  0.013  1.0
  Al  Al6  1  0.835  0.351  0.750  1.0
  Al  Al7  1  0.351  0.835  0.750  1.0
  Cu  Cu8  1  0.838  0.838  0.750  1.0
  Cu  Cu9  1  0.171  0.651  0.250  1.0
  Cu  Cu10  1  0.651  0.171  0.250  1.0
  Cu  Cu11  1  0.170  0.170  0.250  1.0
[/CIF]
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