The material described by Tb(CrAl2)4 crystallizes in the tetragonal I4/mmm space group. Tb(1) is bonded in a 20-coordinate geometry to eight equivalent Cr(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cr(1) is bonded to two equivalent Tb(1), two equivalent Cr(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted CrTb2Al8Cr2 cuboctahedra that share corners with eight equivalent Al(2)Tb2Al6Cr4 cuboctahedra, corners with ten equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, edges with four equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, edges with four equivalent Al(2)Tb2Al6Cr4 cuboctahedra, faces with six equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, and faces with eight equivalent Al(2)Tb2Al6Cr4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Tb(1), four equivalent Cr(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two equivalent Tb(1), four equivalent Cr(1), two equivalent Al(2), and four equivalent Al(1) atoms to form distorted AlTb2Al6Cr4 cuboctahedra that share corners with eight equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, corners with ten equivalent Al(2)Tb2Al6Cr4 cuboctahedra, edges with three equivalent Al(2)Tb2Al6Cr4 cuboctahedra, edges with four equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, faces with seven equivalent Al(2)Tb2Al6Cr4 cuboctahedra, and faces with eight equivalent Cr(1)Tb2Al8Cr2 cuboctahedra. is represented by the CIF file [CIF]
data_Tb(Al2Cr)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.061
_cell_length_b   6.794
_cell_length_c   6.794
_cell_angle_alpha   82.026
_cell_angle_beta   68.133
_cell_angle_gamma   68.133
_symmetry_Int_Tables_number   1
_cell_volume   201.161
_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
  Tb  Tb0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.336  0.664  1.0
  Al  Al2  1  0.000  0.664  0.336  1.0
  Al  Al3  1  0.664  0.336  0.336  1.0
  Al  Al4  1  0.336  0.664  0.664  1.0
  Al  Al5  1  0.500  0.777  0.223  1.0
  Al  Al6  1  0.500  0.223  0.777  1.0
  Al  Al7  1  0.723  0.777  0.777  1.0
  Al  Al8  1  0.277  0.223  0.223  1.0
  Cr  Cr9  1  0.000  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.000  0.500  1.0
  Cr  Cr11  1  0.500  0.500  0.000  1.0
  Cr  Cr12  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by Tb(CrAl2)4 crystallizes in the tetragonal I4/mmm space group. Tb(1) is bonded in a 20-coordinate geometry to eight equivalent Cr(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Cr(1) is bonded to two equivalent Tb(1), two equivalent Cr(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted CrTb2Al8Cr2 cuboctahedra that share corners with eight equivalent Al(2)Tb2Al6Cr4 cuboctahedra, corners with ten equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, edges with four equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, edges with four equivalent Al(2)Tb2Al6Cr4 cuboctahedra, faces with six equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, and faces with eight equivalent Al(2)Tb2Al6Cr4 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Tb(1), four equivalent Cr(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to two equivalent Tb(1), four equivalent Cr(1), two equivalent Al(2), and four equivalent Al(1) atoms to form distorted AlTb2Al6Cr4 cuboctahedra that share corners with eight equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, corners with ten equivalent Al(2)Tb2Al6Cr4 cuboctahedra, edges with three equivalent Al(2)Tb2Al6Cr4 cuboctahedra, edges with four equivalent Cr(1)Tb2Al8Cr2 cuboctahedra, faces with seven equivalent Al(2)Tb2Al6Cr4 cuboctahedra, and faces with eight equivalent Cr(1)Tb2Al8Cr2 cuboctahedra. is represented by the CIF file [CIF]
data_Tb(Al2Cr)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.061
_cell_length_b   6.794
_cell_length_c   6.794
_cell_angle_alpha   82.026
_cell_angle_beta   68.133
_cell_angle_gamma   68.133
_symmetry_Int_Tables_number   1
_cell_volume   201.161
_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
  Tb  Tb0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.000  0.336  0.664  1.0
  Al  Al2  1  0.000  0.664  0.336  1.0
  Al  Al3  1  0.664  0.336  0.336  1.0
  Al  Al4  1  0.336  0.664  0.664  1.0
  Al  Al5  1  0.500  0.777  0.223  1.0
  Al  Al6  1  0.500  0.223  0.777  1.0
  Al  Al7  1  0.723  0.777  0.777  1.0
  Al  Al8  1  0.277  0.223  0.223  1.0
  Cr  Cr9  1  0.000  0.000  0.500  1.0
  Cr  Cr10  1  0.500  0.000  0.500  1.0
  Cr  Cr11  1  0.500  0.500  0.000  1.0
  Cr  Cr12  1  0.000  0.500  0.000  1.0
[/CIF]
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