data_BaTa3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.04
_cell_length_b   5.04
_cell_length_c   5.04
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaTa3Cu
_chemical_formula_sum   'Ba1 Ta3 Cu1'
_cell_volume   127.88
_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
  Ba  Ba0  1  0.52  0.52  0.52  1.0
  Ta  Ta2  1  0.52  0.0  0.52  1.0
  Ta  Ta3  1  0.52  0.52  0.0  1.0
  Ta  Ta4  1  0.0  0.52  0.52  1.0
  Cu  Cu1  1  0.0  0.0  0.0  1.0

data_BaTa3Cu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.12
_cell_length_b   7.12
_cell_length_c   8.73
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   BaTa3Cu
_chemical_formula_sum   'Ba3 Ta9 Cu3'
_cell_volume   383.63
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Ba  Ba0  3  0.0  0.0  0.52  1.0
  Ta  Ta1  9  0.17  0.35  0.35  1.0
  Cu  Cu2  3  0.0  0.0  0.0  1.0

Ba Ta Ta Ta Cu
Ba Ta Ta Ta Cu 0 3 o o o 0 3 + o o 0 1 o o o 0 1 o + o 0 2 o o o 0 2 o o + 0 4 + + + 1 4 + o + 1 4 + o o 1 4 o o + 1 4 o o o 2 4 + + o 2 4 + o o 2 4 o + o 2 4 o o o 3 4 o + + 3 4 o + o 3 4 o o + 3 4 o o o 
BaTa3Cu is (Cubic) Perovskite structured and crystallizes in the trigonal R3m space group. Ba(1) is bonded to six equivalent Ta(1) atoms to form BaTa6 octahedra that share corners with six equivalent Ba(1)Ta6 octahedra and faces with eight equivalent Cu(1)Ta12 cuboctahedra. The corner-sharing octahedra are not tilted. There are three shorter (2.42 Å) and three longer (2.61 Å) Ba(1)-Ta(1) bond lengths. Ta(1) is bonded in a distorted linear geometry to two equivalent Ba(1) and four equivalent Cu(1) atoms. There are a spread of Ta(1)-Cu(1) bond distances ranging from 3.43-3.70 Å. Cu(1) is bonded to twelve equivalent Ta(1) atoms to form CuTa12 cuboctahedra that share corners with twelve equivalent Cu(1)Ta12 cuboctahedra, faces with six equivalent Cu(1)Ta12 cuboctahedra, and faces with eight equivalent Ba(1)Ta6 octahedra.