The structure described by Sr2CrCu2AlO7 crystallizes in the monoclinic Cm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(5), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(2), one O(4), one O(6), one O(8), and two equivalent O(7) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), and two equivalent O(7) atoms to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), and two equivalent O(8) atoms to form corner-sharing CrO4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(6) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Al(1) is bonded in a distorted tetrahedral geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cr(1), and one Cu(2) atom. In the second O site, O(8) is bonded in a 1-coordinate geometry to one Sr(1), one Sr(2), and one Cr(2) atom. In the third O site, O(1) is bonded to two equivalent Sr(1), one Cr(1), and one Cr(2) atom to form distorted corner-sharing OSr2Cr2 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Sr(2), one Cr(1), and one Cr(2) atom to form distorted corner-sharing OSr2Cr2 tetrahedra. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Cu(1), one Cu(2), and one Al(1) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(1), one Cu(2), and one Al(1) atom. In the seventh O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Cu(1), one Cu(2), and one Al(1) atom. In the eighth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(1), one Cu(2), and one Al(1) atom. is represented by the CIF card [CIF]
data_Sr2AlCrCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.104
_cell_length_b   12.104
_cell_length_c   5.384
_cell_angle_alpha   77.303
_cell_angle_beta   77.303
_cell_angle_gamma   143.139
_symmetry_Int_Tables_number   1
_cell_volume   340.138
_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  0.661  0.872  0.973  1.0
  Sr  Sr1  1  0.338  0.129  0.008  1.0
  Sr  Sr2  1  0.129  0.338  0.008  1.0
  Sr  Sr3  1  0.872  0.661  0.973  1.0
  Al  Al4  1  0.002  0.503  0.987  1.0
  Al  Al5  1  0.503  0.002  0.987  1.0
  Cr  Cr6  1  0.310  0.310  0.467  1.0
  Cr  Cr7  1  0.677  0.677  0.603  1.0
  Cu  Cu8  1  0.555  0.944  0.488  1.0
  Cu  Cu9  1  0.447  0.061  0.483  1.0
  Cu  Cu10  1  0.061  0.447  0.483  1.0
  Cu  Cu11  1  0.944  0.555  0.488  1.0
  O  O12  1  0.637  0.637  0.982  1.0
  O  O13  1  0.365  0.365  0.788  1.0
  O  O14  1  0.731  0.124  0.631  1.0
  O  O15  1  0.269  0.877  0.984  1.0
  O  O16  1  0.877  0.269  0.984  1.0
  O  O17  1  0.124  0.731  0.631  1.0
  O  O18  1  0.384  0.773  0.333  1.0
  O  O19  1  0.619  0.232  0.985  1.0
  O  O20  1  0.232  0.619  0.985  1.0
  O  O21  1  0.773  0.384  0.333  1.0
  O  O22  1  0.131  0.283  0.515  1.0
  O  O23  1  0.867  0.726  0.413  1.0
  O  O24  1  0.726  0.867  0.413  1.0
  O  O25  1  0.283  0.131  0.515  1.0
[/CIF]
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The structure described by Sr2CrCu2AlO7 crystallizes in the monoclinic Cm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(5), one O(8), and two equivalent O(7) atoms. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one O(2), one O(4), one O(6), one O(8), and two equivalent O(7) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), and two equivalent O(7) atoms to form corner-sharing CrO4 tetrahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), and two equivalent O(8) atoms to form corner-sharing CrO4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), and one O(6) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Al(1) is bonded in a distorted tetrahedral geometry to one O(3), one O(4), one O(5), and one O(6) atom. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), one Cr(1), and one Cu(2) atom. In the second O site, O(8) is bonded in a 1-coordinate geometry to one Sr(1), one Sr(2), and one Cr(2) atom. In the third O site, O(1) is bonded to two equivalent Sr(1), one Cr(1), and one Cr(2) atom to form distorted corner-sharing OSr2Cr2 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Sr(2), one Cr(1), and one Cr(2) atom to form distorted corner-sharing OSr2Cr2 tetrahedra. In the fifth O site, O(3) is bonded in a 4-coordinate geometry to one Sr(1), one Cu(1), one Cu(2), and one Al(1) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(1), one Cu(2), and one Al(1) atom. In the seventh O site, O(5) is bonded in a 4-coordinate geometry to one Sr(1), one Cu(1), one Cu(2), and one Al(1) atom. In the eighth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(1), one Cu(2), and one Al(1) atom. is represented by the CIF card [CIF]
data_Sr2AlCrCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.104
_cell_length_b   12.104
_cell_length_c   5.384
_cell_angle_alpha   77.303
_cell_angle_beta   77.303
_cell_angle_gamma   143.139
_symmetry_Int_Tables_number   1
_cell_volume   340.138
_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  0.661  0.872  0.973  1.0
  Sr  Sr1  1  0.338  0.129  0.008  1.0
  Sr  Sr2  1  0.129  0.338  0.008  1.0
  Sr  Sr3  1  0.872  0.661  0.973  1.0
  Al  Al4  1  0.002  0.503  0.987  1.0
  Al  Al5  1  0.503  0.002  0.987  1.0
  Cr  Cr6  1  0.310  0.310  0.467  1.0
  Cr  Cr7  1  0.677  0.677  0.603  1.0
  Cu  Cu8  1  0.555  0.944  0.488  1.0
  Cu  Cu9  1  0.447  0.061  0.483  1.0
  Cu  Cu10  1  0.061  0.447  0.483  1.0
  Cu  Cu11  1  0.944  0.555  0.488  1.0
  O  O12  1  0.637  0.637  0.982  1.0
  O  O13  1  0.365  0.365  0.788  1.0
  O  O14  1  0.731  0.124  0.631  1.0
  O  O15  1  0.269  0.877  0.984  1.0
  O  O16  1  0.877  0.269  0.984  1.0
  O  O17  1  0.124  0.731  0.631  1.0
  O  O18  1  0.384  0.773  0.333  1.0
  O  O19  1  0.619  0.232  0.985  1.0
  O  O20  1  0.232  0.619  0.985  1.0
  O  O21  1  0.773  0.384  0.333  1.0
  O  O22  1  0.131  0.283  0.515  1.0
  O  O23  1  0.867  0.726  0.413  1.0
  O  O24  1  0.726  0.867  0.413  1.0
  O  O25  1  0.283  0.131  0.515  1.0
[/CIF]
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