The material structure described by Er2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), and four equivalent O(2) atoms. In the second Er site, Er(2) is bonded to one O(3), two equivalent O(2), and four equivalent O(1) atoms to form distorted ErO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Er(2)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. Cu(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Er(2)O7 pentagonal bipyramids and  an edgeedge with one Er(2)O7 pentagonal bipyramid. There are three inequivalent O sites. In the first O site, O(3) is bonded to three equivalent Ba(1), one Er(1), one Er(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Er2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the second O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Er(1), two equivalent Er(2), and one Cu(1) atom. In the third O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Er(2), two equivalent Er(1), and one Cu(1) atom. is represented by the CIF file [CIF]
data_BaEr2CuO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.672
_cell_length_b   7.183
_cell_length_c   12.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.403
_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
  Ba  Ba0  1  0.250  0.933  0.904  1.0
  Ba  Ba1  1  0.750  0.067  0.096  1.0
  Ba  Ba2  1  0.750  0.433  0.596  1.0
  Ba  Ba3  1  0.250  0.567  0.404  1.0
  Er  Er4  1  0.250  0.111  0.287  1.0
  Er  Er5  1  0.750  0.889  0.713  1.0
  Er  Er6  1  0.750  0.611  0.213  1.0
  Er  Er7  1  0.250  0.389  0.787  1.0
  Er  Er8  1  0.250  0.396  0.074  1.0
  Er  Er9  1  0.750  0.604  0.926  1.0
  Er  Er10  1  0.750  0.896  0.426  1.0
  Er  Er11  1  0.250  0.104  0.574  1.0
  Cu  Cu12  1  0.250  0.720  0.661  1.0
  Cu  Cu13  1  0.750  0.280  0.339  1.0
  Cu  Cu14  1  0.750  0.220  0.839  1.0
  Cu  Cu15  1  0.250  0.780  0.161  1.0
  O  O16  1  0.996  0.159  0.431  1.0
  O  O17  1  0.496  0.841  0.569  1.0
  O  O18  1  0.004  0.659  0.069  1.0
  O  O19  1  0.504  0.341  0.931  1.0
  O  O20  1  0.004  0.841  0.569  1.0
  O  O21  1  0.504  0.159  0.431  1.0
  O  O22  1  0.996  0.341  0.931  1.0
  O  O23  1  0.496  0.659  0.069  1.0
  O  O24  1  0.503  0.355  0.228  1.0
  O  O25  1  0.003  0.645  0.772  1.0
  O  O26  1  0.497  0.855  0.272  1.0
  O  O27  1  0.997  0.145  0.728  1.0
  O  O28  1  0.497  0.645  0.772  1.0
  O  O29  1  0.997  0.355  0.228  1.0
  O  O30  1  0.503  0.145  0.728  1.0
  O  O31  1  0.003  0.855  0.272  1.0
  O  O32  1  0.250  0.085  0.100  1.0
  O  O33  1  0.750  0.915  0.900  1.0
  O  O34  1  0.750  0.585  0.400  1.0
  O  O35  1  0.250  0.415  0.600  1.0
[/CIF]
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The material structure described by Er2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), and four equivalent O(2) atoms. In the second Er site, Er(2) is bonded to one O(3), two equivalent O(2), and four equivalent O(1) atoms to form distorted ErO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Er(2)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. Cu(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Er(2)O7 pentagonal bipyramids and  an edgeedge with one Er(2)O7 pentagonal bipyramid. There are three inequivalent O sites. In the first O site, O(3) is bonded to three equivalent Ba(1), one Er(1), one Er(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Er2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the second O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Er(1), two equivalent Er(2), and one Cu(1) atom. In the third O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Er(2), two equivalent Er(1), and one Cu(1) atom. is represented by the CIF file [CIF]
data_BaEr2CuO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.672
_cell_length_b   7.183
_cell_length_c   12.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   496.403
_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
  Ba  Ba0  1  0.250  0.933  0.904  1.0
  Ba  Ba1  1  0.750  0.067  0.096  1.0
  Ba  Ba2  1  0.750  0.433  0.596  1.0
  Ba  Ba3  1  0.250  0.567  0.404  1.0
  Er  Er4  1  0.250  0.111  0.287  1.0
  Er  Er5  1  0.750  0.889  0.713  1.0
  Er  Er6  1  0.750  0.611  0.213  1.0
  Er  Er7  1  0.250  0.389  0.787  1.0
  Er  Er8  1  0.250  0.396  0.074  1.0
  Er  Er9  1  0.750  0.604  0.926  1.0
  Er  Er10  1  0.750  0.896  0.426  1.0
  Er  Er11  1  0.250  0.104  0.574  1.0
  Cu  Cu12  1  0.250  0.720  0.661  1.0
  Cu  Cu13  1  0.750  0.280  0.339  1.0
  Cu  Cu14  1  0.750  0.220  0.839  1.0
  Cu  Cu15  1  0.250  0.780  0.161  1.0
  O  O16  1  0.996  0.159  0.431  1.0
  O  O17  1  0.496  0.841  0.569  1.0
  O  O18  1  0.004  0.659  0.069  1.0
  O  O19  1  0.504  0.341  0.931  1.0
  O  O20  1  0.004  0.841  0.569  1.0
  O  O21  1  0.504  0.159  0.431  1.0
  O  O22  1  0.996  0.341  0.931  1.0
  O  O23  1  0.496  0.659  0.069  1.0
  O  O24  1  0.503  0.355  0.228  1.0
  O  O25  1  0.003  0.645  0.772  1.0
  O  O26  1  0.497  0.855  0.272  1.0
  O  O27  1  0.997  0.145  0.728  1.0
  O  O28  1  0.497  0.645  0.772  1.0
  O  O29  1  0.997  0.355  0.228  1.0
  O  O30  1  0.503  0.145  0.728  1.0
  O  O31  1  0.003  0.855  0.272  1.0
  O  O32  1  0.250  0.085  0.100  1.0
  O  O33  1  0.750  0.915  0.900  1.0
  O  O34  1  0.750  0.585  0.400  1.0
  O  O35  1  0.250  0.415  0.600  1.0
[/CIF]
.