data_Eu2CuO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.54
_cell_length_b   6.54
_cell_length_c   6.54
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Eu2CuO4
_chemical_formula_sum   'Eu4 Cu2 O8'
_cell_volume   197.85
_cell_formula_units_Z   2
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
  Eu  Eu2  1  0.47  0.47  0.78  1.0
  Eu  Eu3  1  0.78  0.78  0.78  1.0
  Eu  Eu4  1  0.78  0.47  0.47  1.0
  Eu  Eu5  1  0.47  0.78  0.47  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.31  0.31  0.31  1.0
  O  O6  1  0.72  0.72  0.16  1.0
  O  O7  1  0.4  0.4  0.4  1.0
  O  O8  1  0.4  0.85  0.85  1.0
  O  O9  1  0.85  0.4  0.85  1.0
  O  O10  1  0.72  0.16  0.72  1.0
  O  O11  1  0.16  0.16  0.16  1.0
  O  O12  1  0.16  0.72  0.72  1.0
  O  O13  1  0.85  0.85  0.4  1.0

data_Eu2CuO4
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.54
_cell_length_b   6.54
_cell_length_c   16.02
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Eu2CuO4
_chemical_formula_sum   'Eu12 Cu6 O24'
_cell_volume   593.55
_cell_formula_units_Z   6
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
  Eu  Eu0  9  0.1  0.21  0.43  1.0
  Eu  Eu1  3  0.0  0.0  0.22  1.0
  Cu  Cu2  3  0.0  0.0  0.0  1.0
  Cu  Cu3  3  0.0  0.0  0.69  1.0
  O  O4  9  0.04  0.52  0.8  1.0
  O  O5  9  0.19  0.37  0.97  1.0
  O  O6  3  0.0  0.0  0.6  1.0
  O  O7  3  0.0  0.0  0.84  1.0

Eu Eu Eu Eu Cu Cu O O O O O O O O
Eu2CuO4 crystallizes in the trigonal R3m space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 2-coordinate geometry to one O(4), two equivalent O(1), and two equivalent O(3) atoms. The Eu(1)-O(4) bond length is 2.90 Å. Both Eu(1)-O(1) bond lengths are 1.95 Å. Both Eu(1)-O(3) bond lengths are 2.51 Å. In the second Eu site, Eu(2) is bonded in an octahedral geometry to three equivalent O(1) and three equivalent O(3) atoms. All Eu(2)-O(1) bond lengths are 2.13 Å. All Eu(2)-O(3) bond lengths are 2.13 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one O(4) and three equivalent O(3) atoms. The Cu(1)-O(4) bond length is 2.55 Å. All Cu(1)-O(3) bond lengths are 2.16 Å. In the second Cu site, Cu(2) is bonded in a distorted single-bond geometry to one O(2) and one O(4) atom. The Cu(2)-O(2) bond length is 1.45 Å. The Cu(2)-O(4) bond length is 2.45 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Eu(2) and two equivalent Eu(1) atoms. In the second O site, O(2) is bonded in a single-bond geometry to one Cu(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Eu(2), two equivalent Eu(1), and one Cu(1) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to three equivalent Eu(1), one Cu(1), and one Cu(2) atom.