data_Sr4ZrCd
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.06
_cell_length_b   7.06
_cell_length_c   7.06
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sr4ZrCd
_chemical_formula_sum   'Sr4 Zr1 Cd1'
_cell_volume   248.31
_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
  Sr  Sr1  1  0.73  0.73  0.24  1.0
  Sr  Sr2  1  0.73  0.24  0.73  1.0
  Sr  Sr3  1  0.24  0.73  0.73  1.0
  Sr  Sr4  1  0.24  0.24  0.24  1.0
  Zr  Zr5  1  0.0  0.0  0.0  1.0
  Cd  Cd0  1  0.49  0.49  0.49  1.0

data_Sr4ZrCd
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.06
_cell_length_b   7.06
_cell_length_c   17.28
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Sr4ZrCd
_chemical_formula_sum   'Sr12 Zr3 Cd3'
_cell_volume   744.94
_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
  Sr  Sr0  9  0.17  0.34  0.1  1.0
  Sr  Sr1  3  0.0  0.0  0.76  1.0
  Zr  Zr2  3  0.0  0.0  0.0  1.0
  Cd  Cd3  3  0.0  0.0  0.51  1.0

Sr Sr Sr Sr Zr Cd
Sr Sr Sr Sr Zr Cd 0 5 o o o 0 4 + + o 0 3 + o o 0 3 o + o 1 5 o o o 1 4 + o + 1 3 + o o 1 3 o o + 2 4 o + + 2 5 o o o 2 3 o + o 2 3 o o + 3 4 o o o 
Sr4ZrCd crystallizes in the trigonal R3m space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted linear geometry to two equivalent Sr(2), one Zr(1), and one Cd(1) atom. Both Sr(1)-Sr(2) bond lengths are 3.53 Å. The Sr(1)-Zr(1) bond length is 2.65 Å. The Sr(1)-Cd(1) bond length is 2.40 Å. In the second Sr site, Sr(2) is bonded to six equivalent Sr(1) and one Zr(1) atom to form distorted corner-sharing SrSr6Zr hexagonal pyramids. The Sr(2)-Zr(1) bond length is 4.19 Å. Zr(1) is bonded in a 3-coordinate geometry to one Sr(2) and three equivalent Sr(1) atoms. Cd(1) is bonded in a distorted T-shaped geometry to three equivalent Sr(1) atoms.