data_Na2CuCl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.08
_cell_length_b   5.08
_cell_length_c   5.08
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2CuCl
_chemical_formula_sum   'Na2 Cu1 Cl1'
_cell_volume   92.77
_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
  Na  Na3  1  0.8  0.8  0.8  1.0
  Cu  Cu1  1  0.39  0.39  0.39  1.0
  Cl  Cl0  1  0.59  0.59  0.59  1.0

data_Na2CuCl
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.08
_cell_length_b   5.08
_cell_length_c   12.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Na2CuCl
_chemical_formula_sum   'Na6 Cu3 Cl3'
_cell_volume   278.3
_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
  Na  Na0  3  0.0  0.0  0.0  1.0
  Na  Na1  3  0.0  0.0  0.2  1.0
  Cu  Cu2  3  0.0  0.0  0.61  1.0
  Cl  Cl3  3  0.0  0.0  0.41  1.0

Na Na Cu Cl
Na Na Cu Cl 0 1 - - - 0 1 - - o 0 1 o - - 0 1 - o - 0 3 - - o 0 3 - o - 0 3 o - - 0 2 - o o 0 2 o - o 0 2 o o - 1 3 o o o 1 2 o o + 1 2 o + o 1 2 + o o 2 3 o - o 2 3 - o o 2 3 o o - 2 3 o o o 
Na2CuCl crystallizes in the trigonal R3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one Na(2), three equivalent Cu(1), and three equivalent Cl(1) atoms. The Na(1)-Na(2) bond length is 2.53 Å. All Na(1)-Cu(1) bond lengths are 3.02 Å. All Na(1)-Cl(1) bond lengths are 3.07 Å. In the second Na site, Na(2) is bonded in a distorted single-bond geometry to one Na(1), three equivalent Cu(1), and one Cl(1) atom. All Na(2)-Cu(1) bond lengths are 3.07 Å. The Na(2)-Cl(1) bond length is 2.53 Å. Cu(1) is bonded in a 7-coordinate geometry to three equivalent Na(1), three equivalent Na(2), and one Cl(1) atom. The Cu(1)-Cl(1) bond length is 2.53 Å. Cl(1) is bonded in a 5-coordinate geometry to one Na(2), three equivalent Na(1), and one Cu(1) atom.