data_SrZr2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   5.16
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrZr2Cu
_chemical_formula_sum   'Sr1 Zr2 Cu1'
_cell_volume   97.3
_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  0.83  0.83  0.83  1.0
  Zr  Zr2  1  0.65  0.65  0.65  1.0
  Zr  Zr3  1  0.48  0.48  0.48  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0

data_SrZr2Cu
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   12.65
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SrZr2Cu
_chemical_formula_sum   'Sr3 Zr6 Cu3'
_cell_volume   291.9
_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  3  0.0  0.0  0.17  1.0
  Zr  Zr1  3  0.0  0.0  0.35  1.0
  Zr  Zr2  3  0.0  0.0  0.52  1.0
  Cu  Cu3  3  0.0  0.0  0.0  1.0

Sr Zr Zr Cu
Sr Zr Zr Cu 0 1 o o o 0 3 + + + 1 2 o o o 
SrZr2Cu crystallizes in the trigonal R3m space group. Sr(1) is bonded in a distorted linear geometry to one Zr(1), three equivalent Zr(2), and one Cu(1) atom. The Sr(1)-Zr(1) bond length is 2.21 Å. All Sr(1)-Zr(2) bond lengths are 2.99 Å. The Sr(1)-Cu(1) bond length is 2.21 Å. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one Sr(1), one Zr(2), and three equivalent Cu(1) atoms to form distorted corner-sharing ZrSrZrCu3 trigonal bipyramids. The Zr(1)-Zr(2) bond length is 2.21 Å. All Zr(1)-Cu(1) bond lengths are 2.99 Å. In the second Zr site, Zr(2) is bonded in a 7-coordinate geometry to three equivalent Sr(1), one Zr(1), and three equivalent Cu(1) atoms. All Zr(2)-Cu(1) bond lengths are 3.48 Å. Cu(1) is bonded in a distorted single-bond geometry to one Sr(1), three equivalent Zr(1), and three equivalent Zr(2) atoms.