The material described by Eu2Ir2O7 crystallizes in the trigonal R-3m space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(1) and six equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with six equivalent Eu(2)O8 hexagonal bipyramids and edges with six equivalent Ir(1)O6 octahedra. In the second Eu site, Eu(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(1)O8 hexagonal bipyramids, edges with four equivalent Eu(2)O8 hexagonal bipyramids, edges with two equivalent Ir(2)O6 octahedra, and edges with four equivalent Ir(1)O6 octahedra. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form IrO6 octahedra that share corners with two equivalent Ir(2)O6 octahedra, corners with four equivalent Ir(1)O6 octahedra, edges with two equivalent Eu(1)O8 hexagonal bipyramids, and edges with four equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. In the second Ir site, Ir(2) is bonded to six equivalent O(2) atoms to form IrO6 octahedra that share corners with six equivalent Ir(1)O6 octahedra and edges with six equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Eu(1) and three equivalent Eu(2) atoms to form OEu4 tetrahedra that share corners with four equivalent O(1)Eu4 tetrahedra, corners with six equivalent O(2)Eu2Ir2 tetrahedra, corners with six equivalent O(3)Eu2Ir2 tetrahedra, edges with three equivalent O(2)Eu2Ir2 tetrahedra, and edges with three equivalent O(3)Eu2Ir2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Eu(2), one Ir(1), and one Ir(2) atom to form distorted OEu2Ir2 tetrahedra that share corners with two equivalent O(1)Eu4 tetrahedra, corners with four equivalent O(3)Eu2Ir2 tetrahedra, corners with eight equivalent O(2)Eu2Ir2 tetrahedra,  an edgeedge with one O(1)Eu4 tetrahedra, edges with two equivalent O(2)Eu2Ir2 tetrahedra, and edges with two equivalent O(3)Eu2Ir2 tetrahedra. In the third O site, O(3) is bonded to one Eu(1), one Eu(2), and two equivalent Ir(1) atoms to form distorted OEu2Ir2 tetrahedra that share corners with two equivalent O(1)Eu4 tetrahedra, corners with four equivalent O(2)Eu2Ir2 tetrahedra, corners with eight equivalent O(3)Eu2Ir2 tetrahedra,  an edgeedge with one O(1)Eu4 tetrahedra, edges with two equivalent O(2)Eu2Ir2 tetrahedra, and edges with two equivalent O(3)Eu2Ir2 tetrahedra. is represented by the CIF file [CIF]
data_Eu2Ir2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.308
_cell_length_b   7.308
_cell_length_c   7.308
_cell_angle_alpha   60.010
_cell_angle_beta   60.010
_cell_angle_gamma   60.013
_symmetry_Int_Tables_number   1
_cell_volume   276.065
_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  Eu0  1  0.625  0.625  0.625  1.0
  Eu  Eu1  1  0.125  0.625  0.625  1.0
  Eu  Eu2  1  0.625  0.125  0.625  1.0
  Eu  Eu3  1  0.625  0.625  0.125  1.0
  Ir  Ir4  1  0.625  0.125  0.125  1.0
  Ir  Ir5  1  0.125  0.125  0.125  1.0
  Ir  Ir6  1  0.125  0.125  0.625  1.0
  Ir  Ir7  1  0.125  0.625  0.125  1.0
  O  O8  1  0.500  0.500  0.499  1.0
  O  O9  1  0.204  0.796  0.204  1.0
  O  O10  1  0.046  0.454  0.046  1.0
  O  O11  1  0.204  0.204  0.796  1.0
  O  O12  1  0.796  0.796  0.204  1.0
  O  O13  1  0.046  0.454  0.454  1.0
  O  O14  1  0.454  0.046  0.046  1.0
  O  O15  1  0.796  0.204  0.204  1.0
  O  O16  1  0.454  0.454  0.046  1.0
  O  O17  1  0.204  0.796  0.796  1.0
  O  O18  1  0.750  0.750  0.751  1.0
  O  O19  1  0.454  0.046  0.454  1.0
  O  O20  1  0.046  0.046  0.454  1.0
  O  O21  1  0.796  0.204  0.796  1.0
[/CIF]
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The material described by Eu2Ir2O7 crystallizes in the trigonal R-3m space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(1) and six equivalent O(3) atoms to form distorted EuO8 hexagonal bipyramids that share edges with six equivalent Eu(2)O8 hexagonal bipyramids and edges with six equivalent Ir(1)O6 octahedra. In the second Eu site, Eu(2) is bonded to two equivalent O(1), two equivalent O(3), and four equivalent O(2) atoms to form distorted EuO8 hexagonal bipyramids that share edges with two equivalent Eu(1)O8 hexagonal bipyramids, edges with four equivalent Eu(2)O8 hexagonal bipyramids, edges with two equivalent Ir(2)O6 octahedra, and edges with four equivalent Ir(1)O6 octahedra. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form IrO6 octahedra that share corners with two equivalent Ir(2)O6 octahedra, corners with four equivalent Ir(1)O6 octahedra, edges with two equivalent Eu(1)O8 hexagonal bipyramids, and edges with four equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. In the second Ir site, Ir(2) is bonded to six equivalent O(2) atoms to form IrO6 octahedra that share corners with six equivalent Ir(1)O6 octahedra and edges with six equivalent Eu(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Eu(1) and three equivalent Eu(2) atoms to form OEu4 tetrahedra that share corners with four equivalent O(1)Eu4 tetrahedra, corners with six equivalent O(2)Eu2Ir2 tetrahedra, corners with six equivalent O(3)Eu2Ir2 tetrahedra, edges with three equivalent O(2)Eu2Ir2 tetrahedra, and edges with three equivalent O(3)Eu2Ir2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Eu(2), one Ir(1), and one Ir(2) atom to form distorted OEu2Ir2 tetrahedra that share corners with two equivalent O(1)Eu4 tetrahedra, corners with four equivalent O(3)Eu2Ir2 tetrahedra, corners with eight equivalent O(2)Eu2Ir2 tetrahedra,  an edgeedge with one O(1)Eu4 tetrahedra, edges with two equivalent O(2)Eu2Ir2 tetrahedra, and edges with two equivalent O(3)Eu2Ir2 tetrahedra. In the third O site, O(3) is bonded to one Eu(1), one Eu(2), and two equivalent Ir(1) atoms to form distorted OEu2Ir2 tetrahedra that share corners with two equivalent O(1)Eu4 tetrahedra, corners with four equivalent O(2)Eu2Ir2 tetrahedra, corners with eight equivalent O(3)Eu2Ir2 tetrahedra,  an edgeedge with one O(1)Eu4 tetrahedra, edges with two equivalent O(2)Eu2Ir2 tetrahedra, and edges with two equivalent O(3)Eu2Ir2 tetrahedra. is represented by the CIF file [CIF]
data_Eu2Ir2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.308
_cell_length_b   7.308
_cell_length_c   7.308
_cell_angle_alpha   60.010
_cell_angle_beta   60.010
_cell_angle_gamma   60.013
_symmetry_Int_Tables_number   1
_cell_volume   276.065
_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  Eu0  1  0.625  0.625  0.625  1.0
  Eu  Eu1  1  0.125  0.625  0.625  1.0
  Eu  Eu2  1  0.625  0.125  0.625  1.0
  Eu  Eu3  1  0.625  0.625  0.125  1.0
  Ir  Ir4  1  0.625  0.125  0.125  1.0
  Ir  Ir5  1  0.125  0.125  0.125  1.0
  Ir  Ir6  1  0.125  0.125  0.625  1.0
  Ir  Ir7  1  0.125  0.625  0.125  1.0
  O  O8  1  0.500  0.500  0.499  1.0
  O  O9  1  0.204  0.796  0.204  1.0
  O  O10  1  0.046  0.454  0.046  1.0
  O  O11  1  0.204  0.204  0.796  1.0
  O  O12  1  0.796  0.796  0.204  1.0
  O  O13  1  0.046  0.454  0.454  1.0
  O  O14  1  0.454  0.046  0.046  1.0
  O  O15  1  0.796  0.204  0.204  1.0
  O  O16  1  0.454  0.454  0.046  1.0
  O  O17  1  0.204  0.796  0.796  1.0
  O  O18  1  0.750  0.750  0.751  1.0
  O  O19  1  0.454  0.046  0.454  1.0
  O  O20  1  0.046  0.046  0.454  1.0
  O  O21  1  0.796  0.204  0.796  1.0
[/CIF]
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