The compound described by Sr2YFeCu2O7 crystallizes in the orthorhombic Pmmm space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. Fe(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Cu(1) is bonded to one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing CuO5 square pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Sr(1) and two equivalent Fe(1) atoms to form distorted OSr4Fe2 octahedra that share corners with two equivalent O(1)Sr4Fe2 octahedra, corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with eight equivalent O(2)Sr4FeCu octahedra, edges with two equivalent O(3)Sr2Y2Cu2 octahedra, edges with two equivalent O(1)Sr4Fe2 octahedra, and faces with four equivalent O(2)Sr4FeCu octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the second O site, O(2) is bonded to four equivalent Sr(1), one Fe(1), and one Cu(1) atom to form distorted OSr4FeCu octahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with four equivalent O(1)Sr4Fe2 octahedra, corners with five equivalent O(2)Sr4FeCu octahedra, edges with four equivalent O(2)Sr4FeCu octahedra, faces with two equivalent O(3)Sr2Y2Cu2 octahedra, and faces with two equivalent O(1)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the third 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 two equivalent O(1)Sr4Fe2 octahedra, corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with four equivalent O(2)Sr4FeCu octahedra,  an edgeedge with one O(1)Sr4Fe2 octahedra, edges with three equivalent O(3)Sr2Y2Cu2 octahedra, and faces with two equivalent O(2)Sr4FeCu octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YFeCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.759
_cell_length_b   11.604
_cell_length_c   3.886
_cell_angle_alpha   90.000
_cell_angle_beta   90.010
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   169.498
_cell_formula_units_Z   1
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  0.500  0.812  0.500  1.0
  Sr  Sr1  1  0.500  0.188  0.500  1.0
  Y  Y2  1  0.500  0.500  0.500  1.0
  Fe  Fe3  1  1.000  0.000  1.000  1.0
  Cu  Cu4  1  0.000  0.648  1.000  1.0
  Cu  Cu5  1  0.000  0.352  0.000  1.0
  O  O6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.000  0.838  0.000  1.0
  O  O8  1  0.000  0.162  0.000  1.0
  O  O9  1  1.000  0.628  0.500  1.0
  O  O10  1  0.000  0.372  0.500  1.0
  O  O11  1  0.500  0.624  0.000  1.0
  O  O12  1  0.500  0.376  0.000  1.0
[/CIF]
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The compound described by Sr2YFeCu2O7 crystallizes in the orthorhombic Pmmm space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(2) atoms. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. Fe(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. Cu(1) is bonded to one O(2), two equivalent O(3), and two equivalent O(4) atoms to form corner-sharing CuO5 square pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Sr(1) and two equivalent Fe(1) atoms to form distorted OSr4Fe2 octahedra that share corners with two equivalent O(1)Sr4Fe2 octahedra, corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with eight equivalent O(2)Sr4FeCu octahedra, edges with two equivalent O(3)Sr2Y2Cu2 octahedra, edges with two equivalent O(1)Sr4Fe2 octahedra, and faces with four equivalent O(2)Sr4FeCu octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the second O site, O(2) is bonded to four equivalent Sr(1), one Fe(1), and one Cu(1) atom to form distorted OSr4FeCu octahedra that share corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with four equivalent O(1)Sr4Fe2 octahedra, corners with five equivalent O(2)Sr4FeCu octahedra, edges with four equivalent O(2)Sr4FeCu octahedra, faces with two equivalent O(3)Sr2Y2Cu2 octahedra, and faces with two equivalent O(1)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-68°. In the third 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 two equivalent O(1)Sr4Fe2 octahedra, corners with four equivalent O(3)Sr2Y2Cu2 octahedra, corners with four equivalent O(2)Sr4FeCu octahedra,  an edgeedge with one O(1)Sr4Fe2 octahedra, edges with three equivalent O(3)Sr2Y2Cu2 octahedra, and faces with two equivalent O(2)Sr4FeCu octahedra. The corner-sharing octahedral tilt angles range from 0-57°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Y(1), and two equivalent Cu(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YFeCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.759
_cell_length_b   11.604
_cell_length_c   3.886
_cell_angle_alpha   90.000
_cell_angle_beta   90.010
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   169.498
_cell_formula_units_Z   1
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  0.500  0.812  0.500  1.0
  Sr  Sr1  1  0.500  0.188  0.500  1.0
  Y  Y2  1  0.500  0.500  0.500  1.0
  Fe  Fe3  1  1.000  0.000  1.000  1.0
  Cu  Cu4  1  0.000  0.648  1.000  1.0
  Cu  Cu5  1  0.000  0.352  0.000  1.0
  O  O6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.000  0.838  0.000  1.0
  O  O8  1  0.000  0.162  0.000  1.0
  O  O9  1  1.000  0.628  0.500  1.0
  O  O10  1  0.000  0.372  0.500  1.0
  O  O11  1  0.500  0.624  0.000  1.0
  O  O12  1  0.500  0.376  0.000  1.0
[/CIF]
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