data_NaCu2Sb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.66
_cell_length_b   4.66
_cell_length_c   4.66
_cell_angle_alpha   121.26
_cell_angle_beta   121.26
_cell_angle_gamma   87.84
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaCu2Sb
_chemical_formula_sum   'Na1 Cu2 Sb1'
_cell_volume   69.96
_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
  Na  Na2  1  0.0  0.0  0.0  1.0
  Cu  Cu0  1  0.0  0.28  0.68  1.0
  Cu  Cu1  1  0.28  0.0  0.68  1.0
  Sb  Sb3  1  0.0  0.0  0.35  1.0

data_NaCu2Sb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.46
_cell_length_b   6.46
_cell_length_c   4.66
_cell_angle_alpha   90.0
_cell_angle_beta   133.92
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaCu2Sb
_chemical_formula_sum   'Na2 Cu4 Sb2'
_cell_volume   139.92
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Na  Na0  2  0.0  0.0  0.0  1.0
  Cu  Cu1  4  0.36  0.36  0.39  1.0
  Sb  Sb2  2  0.0  0.0  0.35  1.0

Na Cu Cu Sb