The compound described by Er2EuO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form a mixture of corner and edge-sharing ErO6 octahedra. The corner-sharing octahedral tilt angles range from 50-64°. In the second Er site, Er(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing ErO6 octahedra. The corner-sharing octahedral tilt angles range from 50-64°. Eu(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Er(2) and two equivalent Eu(1) atoms to form a mixture of distorted corner and edge-sharing OEu2Er3 trigonal bipyramids. In the second O site, O(2) is bonded to three equivalent Er(1) and two equivalent Eu(1) atoms to form a mixture of corner and edge-sharing OEu2Er3 square pyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Er(1), two equivalent Er(2), and two equivalent Eu(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Er(2), two equivalent Er(1), and two equivalent Eu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuEr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.385
_cell_length_b   9.989
_cell_length_c   11.870
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.362
_cell_formula_units_Z   4
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  0.250  0.748  0.149  1.0
  Eu  Eu1  1  0.750  0.252  0.851  1.0
  Eu  Eu2  1  0.750  0.752  0.649  1.0
  Eu  Eu3  1  0.250  0.248  0.351  1.0
  Er  Er4  1  0.250  0.576  0.889  1.0
  Er  Er5  1  0.750  0.424  0.111  1.0
  Er  Er6  1  0.750  0.924  0.389  1.0
  Er  Er7  1  0.250  0.076  0.611  1.0
  Er  Er8  1  0.250  0.078  0.112  1.0
  Er  Er9  1  0.750  0.922  0.888  1.0
  Er  Er10  1  0.750  0.422  0.612  1.0
  Er  Er11  1  0.250  0.578  0.388  1.0
  O  O12  1  0.250  0.576  0.578  1.0
  O  O13  1  0.750  0.424  0.422  1.0
  O  O14  1  0.750  0.924  0.078  1.0
  O  O15  1  0.250  0.076  0.922  1.0
  O  O16  1  0.250  0.873  0.520  1.0
  O  O17  1  0.750  0.127  0.480  1.0
  O  O18  1  0.750  0.627  0.020  1.0
  O  O19  1  0.250  0.373  0.980  1.0
  O  O20  1  0.250  0.788  0.825  1.0
  O  O21  1  0.750  0.212  0.175  1.0
  O  O22  1  0.750  0.712  0.325  1.0
  O  O23  1  0.250  0.288  0.675  1.0
  O  O24  1  0.250  0.986  0.284  1.0
  O  O25  1  0.750  0.014  0.716  1.0
  O  O26  1  0.750  0.514  0.784  1.0
  O  O27  1  0.250  0.486  0.216  1.0
[/CIF]
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The compound described by Er2EuO4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form a mixture of corner and edge-sharing ErO6 octahedra. The corner-sharing octahedral tilt angles range from 50-64°. In the second Er site, Er(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing ErO6 octahedra. The corner-sharing octahedral tilt angles range from 50-64°. Eu(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Er(2) and two equivalent Eu(1) atoms to form a mixture of distorted corner and edge-sharing OEu2Er3 trigonal bipyramids. In the second O site, O(2) is bonded to three equivalent Er(1) and two equivalent Eu(1) atoms to form a mixture of corner and edge-sharing OEu2Er3 square pyramids. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Er(1), two equivalent Er(2), and two equivalent Eu(1) atoms. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Er(2), two equivalent Er(1), and two equivalent Eu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_EuEr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.385
_cell_length_b   9.989
_cell_length_c   11.870
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.362
_cell_formula_units_Z   4
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  0.250  0.748  0.149  1.0
  Eu  Eu1  1  0.750  0.252  0.851  1.0
  Eu  Eu2  1  0.750  0.752  0.649  1.0
  Eu  Eu3  1  0.250  0.248  0.351  1.0
  Er  Er4  1  0.250  0.576  0.889  1.0
  Er  Er5  1  0.750  0.424  0.111  1.0
  Er  Er6  1  0.750  0.924  0.389  1.0
  Er  Er7  1  0.250  0.076  0.611  1.0
  Er  Er8  1  0.250  0.078  0.112  1.0
  Er  Er9  1  0.750  0.922  0.888  1.0
  Er  Er10  1  0.750  0.422  0.612  1.0
  Er  Er11  1  0.250  0.578  0.388  1.0
  O  O12  1  0.250  0.576  0.578  1.0
  O  O13  1  0.750  0.424  0.422  1.0
  O  O14  1  0.750  0.924  0.078  1.0
  O  O15  1  0.250  0.076  0.922  1.0
  O  O16  1  0.250  0.873  0.520  1.0
  O  O17  1  0.750  0.127  0.480  1.0
  O  O18  1  0.750  0.627  0.020  1.0
  O  O19  1  0.250  0.373  0.980  1.0
  O  O20  1  0.250  0.788  0.825  1.0
  O  O21  1  0.750  0.212  0.175  1.0
  O  O22  1  0.750  0.712  0.325  1.0
  O  O23  1  0.250  0.288  0.675  1.0
  O  O24  1  0.250  0.986  0.284  1.0
  O  O25  1  0.750  0.014  0.716  1.0
  O  O26  1  0.750  0.514  0.784  1.0
  O  O27  1  0.250  0.486  0.216  1.0
[/CIF]
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