data_CaCuSb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   5.19
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaCuSb2
_chemical_formula_sum   'Ca1 Cu1 Sb2'
_cell_volume   98.95
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.51  0.51  0.51  1.0
  Sb  Sb2  1  0.67  0.67  0.67  1.0
  Sb  Sb3  1  0.84  0.84  0.84  1.0

data_CaCuSb2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   12.72
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaCuSb2
_chemical_formula_sum   'Ca3 Cu3 Sb6'
_cell_volume   296.85
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Cu  Cu1  3  0.0  0.0  0.49  1.0
  Sb  Sb2  3  0.0  0.0  0.16  1.0
  Sb  Sb3  3  0.0  0.0  0.33  1.0

Ca Cu Sb Sb
CaCuSb2 crystallizes in the trigonal R3m space group. Ca(1) is bonded in a distorted single-bond geometry to one Sb(2) and three equivalent Sb(1) atoms. The Ca(1)-Sb(2) bond length is 2.09 Å. All Ca(1)-Sb(1) bond lengths are 3.00 Å. Cu(1) is bonded in a distorted single-bond geometry to one Sb(1) atom. The Cu(1)-Sb(1) bond length is 2.09 Å. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to three equivalent Ca(1), one Cu(1), and one Sb(2) atom to form corner-sharing SbCa3CuSb trigonal bipyramids. The Sb(1)-Sb(2) bond length is 2.09 Å. In the second Sb site, Sb(2) is bonded in a distorted single-bond geometry to one Ca(1) and one Sb(1) atom.