data_NaCd2As
_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   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaCd2As
_chemical_formula_sum   'Na1 Cd2 As1'
_cell_volume   90.63
_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  Na3  1  0.0  0.0  0.0  1.0
  Cd  Cd1  1  0.78  0.78  0.78  1.0
  Cd  Cd2  1  0.57  0.57  0.57  1.0
  As  As0  1  0.35  0.35  0.35  1.0

data_NaCd2As
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.04
_cell_length_b   5.04
_cell_length_c   12.35
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   NaCd2As
_chemical_formula_sum   'Na3 Cd6 As3'
_cell_volume   271.89
_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
  Cd  Cd1  3  0.0  0.0  0.22  1.0
  Cd  Cd2  3  0.0  0.0  0.43  1.0
  As  As3  3  0.0  0.0  0.65  1.0

Na Cd Cd As
NaCd2As crystallizes in the trigonal R3m space group. Na(1) is bonded in a 10-coordinate geometry to three equivalent Cd(2), four equivalent Cd(1), and three equivalent As(1) atoms. All Na(1)-Cd(2) bond lengths are 3.17 Å. There is one shorter (2.69 Å) and three longer (3.24 Å) Na(1)-Cd(1) bond lengths. All Na(1)-As(1) bond lengths are 2.92 Å. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded in a distorted single-bond geometry to four equivalent Na(1) and three equivalent As(1) atoms. All Cd(1)-As(1) bond lengths are 3.17 Å. In the second Cd site, Cd(2) is bonded in a 1-coordinate geometry to three equivalent Na(1) and four equivalent As(1) atoms. There is one shorter (2.69 Å) and three longer (3.24 Å) Cd(2)-As(1) bond lengths. As(1) is bonded to three equivalent Na(1), three equivalent Cd(1), and four equivalent Cd(2) atoms to form a mixture of distorted face and corner-sharing AsNa3Cd7 trigonal pyramids.