The crystal structure described by Sr2Cu2GaAlO7 crystallizes in the monoclinic Cc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(7), and four equivalent O(6) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(5), and four equivalent O(3) atoms. 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), two equivalent O(4), and two equivalent O(5) atoms. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(6), two equivalent O(1), and two equivalent O(7) atoms. Ga(1) is bonded to one O(3), one O(6), and two equivalent O(2) atoms to form corner-sharing GaO4 tetrahedra. Al(1) is bonded in a distorted tetrahedral geometry to one O(1), one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Cu(2), and one Ga(1) atom. In the second O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Cu(2), and one Al(1) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Cu(2), and one Al(1) atom. In the fourth O site, O(2) is bonded to one Sr(1), one Sr(2), and two equivalent Ga(1) atoms to form distorted corner-sharing OSr2Ga2 tetrahedra. In the fifth O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Sr(2), one Cu(1), and one Ga(1) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Cu(1), and one Al(1) atom. In the seventh O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Cu(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2AlGaCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.179
_cell_length_b   12.179
_cell_length_c   5.294
_cell_angle_alpha   77.585
_cell_angle_beta   77.585
_cell_angle_gamma   25.655
_symmetry_Int_Tables_number   1
_cell_volume   331.599
_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  0.136  0.664  0.852  1.0
  Sr  Sr1  1  0.870  0.330  0.161  1.0
  Sr  Sr2  1  0.664  0.136  0.352  1.0
  Sr  Sr3  1  0.330  0.870  0.661  1.0
  Al  Al4  1  0.491  0.009  0.487  1.0
  Al  Al5  1  0.009  0.491  0.987  1.0
  Ga  Ga6  1  0.681  0.319  0.710  1.0
  Ga  Ga7  1  0.319  0.681  0.210  1.0
  Cu  Cu8  1  0.939  0.445  0.562  1.0
  Cu  Cu9  1  0.558  0.059  0.934  1.0
  Cu  Cu10  1  0.445  0.939  0.062  1.0
  Cu  Cu11  1  0.059  0.558  0.434  1.0
  O  O12  1  0.729  0.874  0.620  1.0
  O  O13  1  0.646  0.354  0.351  1.0
  O  O14  1  0.874  0.729  0.120  1.0
  O  O15  1  0.293  0.857  0.201  1.0
  O  O16  1  0.776  0.611  0.892  1.0
  O  O17  1  0.611  0.776  0.392  1.0
  O  O18  1  0.354  0.646  0.851  1.0
  O  O19  1  0.139  0.260  0.239  1.0
  O  O20  1  0.260  0.139  0.739  1.0
  O  O21  1  0.857  0.293  0.701  1.0
  O  O22  1  0.711  0.140  0.845  1.0
  O  O23  1  0.140  0.711  0.345  1.0
  O  O24  1  0.231  0.382  0.764  1.0
  O  O25  1  0.382  0.231  0.264  1.0
[/CIF]
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The crystal structure described by Sr2Cu2GaAlO7 crystallizes in the monoclinic Cc space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(2), one O(7), and four equivalent O(6) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one O(2), one O(4), one O(5), and four equivalent O(3) atoms. 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), two equivalent O(4), and two equivalent O(5) atoms. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(6), two equivalent O(1), and two equivalent O(7) atoms. Ga(1) is bonded to one O(3), one O(6), and two equivalent O(2) atoms to form corner-sharing GaO4 tetrahedra. Al(1) is bonded in a distorted tetrahedral geometry to one O(1), one O(4), one O(5), and one O(7) atom. There are seven inequivalent O sites. In the first O site, O(6) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Cu(2), and one Ga(1) atom. In the second O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Cu(2), and one Al(1) atom. In the third O site, O(1) is bonded in a 4-coordinate geometry to one Sr(1), two equivalent Cu(2), and one Al(1) atom. In the fourth O site, O(2) is bonded to one Sr(1), one Sr(2), and two equivalent Ga(1) atoms to form distorted corner-sharing OSr2Ga2 tetrahedra. In the fifth O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Sr(2), one Cu(1), and one Ga(1) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(2), two equivalent Cu(1), and one Al(1) atom. In the seventh O site, O(5) is bonded in a 3-coordinate geometry to one Sr(2), two equivalent Cu(1), and one Al(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2AlGaCu2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.179
_cell_length_b   12.179
_cell_length_c   5.294
_cell_angle_alpha   77.585
_cell_angle_beta   77.585
_cell_angle_gamma   25.655
_symmetry_Int_Tables_number   1
_cell_volume   331.599
_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  0.136  0.664  0.852  1.0
  Sr  Sr1  1  0.870  0.330  0.161  1.0
  Sr  Sr2  1  0.664  0.136  0.352  1.0
  Sr  Sr3  1  0.330  0.870  0.661  1.0
  Al  Al4  1  0.491  0.009  0.487  1.0
  Al  Al5  1  0.009  0.491  0.987  1.0
  Ga  Ga6  1  0.681  0.319  0.710  1.0
  Ga  Ga7  1  0.319  0.681  0.210  1.0
  Cu  Cu8  1  0.939  0.445  0.562  1.0
  Cu  Cu9  1  0.558  0.059  0.934  1.0
  Cu  Cu10  1  0.445  0.939  0.062  1.0
  Cu  Cu11  1  0.059  0.558  0.434  1.0
  O  O12  1  0.729  0.874  0.620  1.0
  O  O13  1  0.646  0.354  0.351  1.0
  O  O14  1  0.874  0.729  0.120  1.0
  O  O15  1  0.293  0.857  0.201  1.0
  O  O16  1  0.776  0.611  0.892  1.0
  O  O17  1  0.611  0.776  0.392  1.0
  O  O18  1  0.354  0.646  0.851  1.0
  O  O19  1  0.139  0.260  0.239  1.0
  O  O20  1  0.260  0.139  0.739  1.0
  O  O21  1  0.857  0.293  0.701  1.0
  O  O22  1  0.711  0.140  0.845  1.0
  O  O23  1  0.140  0.711  0.345  1.0
  O  O24  1  0.231  0.382  0.764  1.0
  O  O25  1  0.382  0.231  0.264  1.0
[/CIF]
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