The structure described by Sr2YNiCu2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. Ni(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form NiO4 tetrahedra that share corners with two equivalent Cu(1)O5 square pyramids and corners with two equivalent Ni(1)O4 tetrahedra. Cu(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids and  a cornercorner with one Ni(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Ni(1), and one Cu(1) atom. In the second O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Ni(1) atoms to form distorted OSr2Ni2 tetrahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra and corners with two equivalent O(1)Sr2Ni2 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. In the third O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms. In the fourth O site, O(3) is bonded to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms to form distorted OSr2Y2Cu2 octahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with two equivalent O(1)Sr2Ni2 tetrahedra, and faces with two equivalent O(3)Sr2Y2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-68°. is represented by the CIF file [CIF]
data_Sr2YCu2NiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.182
_cell_length_b   12.182
_cell_length_c   12.182
_cell_angle_alpha   154.265
_cell_angle_beta   153.820
_cell_angle_gamma   37.040
_symmetry_Int_Tables_number   1
_cell_volume   345.823
_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
  Sr  Sr0  1  0.664  0.665  0.023  1.0
  Sr  Sr1  1  0.336  0.359  0.001  1.0
  Sr  Sr2  1  0.142  0.165  0.001  1.0
  Sr  Sr3  1  0.858  0.859  0.023  1.0
  Y  Y4  1  0.000  0.010  0.010  1.0
  Y  Y5  1  0.500  0.510  0.010  1.0
  Cu  Cu6  1  0.571  0.084  0.510  1.0
  Cu  Cu7  1  0.429  0.939  0.513  1.0
  Cu  Cu8  1  0.074  0.584  0.513  1.0
  Cu  Cu9  1  0.926  0.439  0.510  1.0
  Ni  Ni10  1  0.320  0.722  0.542  1.0
  Ni  Ni11  1  0.680  0.222  0.402  1.0
  O  O12  1  0.634  0.870  0.004  1.0
  O  O13  1  0.366  0.370  0.235  1.0
  O  O14  1  0.805  0.819  0.501  1.0
  O  O15  1  0.195  0.695  0.013  1.0
  O  O16  1  0.818  0.319  0.013  1.0
  O  O17  1  0.182  0.195  0.501  1.0
  O  O18  1  0.318  0.330  0.519  1.0
  O  O19  1  0.682  0.201  0.012  1.0
  O  O20  1  0.311  0.830  0.012  1.0
  O  O21  1  0.689  0.701  0.519  1.0
  O  O22  1  0.134  0.709  0.492  1.0
  O  O23  1  0.866  0.358  0.575  1.0
  O  O24  1  0.717  0.209  0.575  1.0
  O  O25  1  0.283  0.858  0.492  1.0
[/CIF]
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The structure described by Sr2YNiCu2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), and four equivalent O(4) atoms. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. Ni(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form NiO4 tetrahedra that share corners with two equivalent Cu(1)O5 square pyramids and corners with two equivalent Ni(1)O4 tetrahedra. Cu(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids and  a cornercorner with one Ni(1)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Ni(1), and one Cu(1) atom. In the second O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Ni(1) atoms to form distorted OSr2Ni2 tetrahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra and corners with two equivalent O(1)Sr2Ni2 tetrahedra. The corner-sharing octahedral tilt angles range from 50-66°. In the third O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms. In the fourth O site, O(3) is bonded to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms to form distorted OSr2Y2Cu2 octahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with two equivalent O(1)Sr2Ni2 tetrahedra, and faces with two equivalent O(3)Sr2Y2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-68°. is represented by the CIF file [CIF]
data_Sr2YCu2NiO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.182
_cell_length_b   12.182
_cell_length_c   12.182
_cell_angle_alpha   154.265
_cell_angle_beta   153.820
_cell_angle_gamma   37.040
_symmetry_Int_Tables_number   1
_cell_volume   345.823
_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
  Sr  Sr0  1  0.664  0.665  0.023  1.0
  Sr  Sr1  1  0.336  0.359  0.001  1.0
  Sr  Sr2  1  0.142  0.165  0.001  1.0
  Sr  Sr3  1  0.858  0.859  0.023  1.0
  Y  Y4  1  0.000  0.010  0.010  1.0
  Y  Y5  1  0.500  0.510  0.010  1.0
  Cu  Cu6  1  0.571  0.084  0.510  1.0
  Cu  Cu7  1  0.429  0.939  0.513  1.0
  Cu  Cu8  1  0.074  0.584  0.513  1.0
  Cu  Cu9  1  0.926  0.439  0.510  1.0
  Ni  Ni10  1  0.320  0.722  0.542  1.0
  Ni  Ni11  1  0.680  0.222  0.402  1.0
  O  O12  1  0.634  0.870  0.004  1.0
  O  O13  1  0.366  0.370  0.235  1.0
  O  O14  1  0.805  0.819  0.501  1.0
  O  O15  1  0.195  0.695  0.013  1.0
  O  O16  1  0.818  0.319  0.013  1.0
  O  O17  1  0.182  0.195  0.501  1.0
  O  O18  1  0.318  0.330  0.519  1.0
  O  O19  1  0.682  0.201  0.012  1.0
  O  O20  1  0.311  0.830  0.012  1.0
  O  O21  1  0.689  0.701  0.519  1.0
  O  O22  1  0.134  0.709  0.492  1.0
  O  O23  1  0.866  0.358  0.575  1.0
  O  O24  1  0.717  0.209  0.575  1.0
  O  O25  1  0.283  0.858  0.492  1.0
[/CIF]
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