The compound described by Sr2Cu2AlSnO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 1-coordinate geometry to one O(2), one O(3), two equivalent O(11), and two equivalent O(13) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(4), one O(6), one O(8), two equivalent O(12), and two equivalent O(14) atoms. In the third Sr site, Sr(3) is bonded in a 3-coordinate geometry to one O(7), two equivalent O(11), and two equivalent O(13) atoms. In the fourth Sr site, Sr(4) is bonded in a 3-coordinate geometry to one O(10), two equivalent O(12), and two equivalent O(14) atoms. There are four 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(5), one O(7), and one O(9) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(10), one O(4), one O(6), and one O(8) atom. In the third Cu site, Cu(3) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), one O(7), and one O(9) atom. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(10), one O(4), one O(6), and one O(8) atom. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 1-coordinate geometry to one O(10), one O(3), one O(5), one O(6), and one O(9) atom. In the second Al site, Al(2) is bonded in a 1-coordinate geometry to one O(10), one O(3), one O(4), one O(7), and one O(8) atom. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(14), and one O(2) atom. In the second Sn site, Sn(2) is bonded in a 4-coordinate geometry to one O(1), one O(12), one O(13), and one O(2) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Sn(1) and one Sn(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Sn(1), and one Sn(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Sr(1), one Cu(1), one Cu(3), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one Al(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(3), one Cu(1), one Cu(3), and one Al(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one Al(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(4), one Cu(2), one Cu(4), one Al(1), and one Al(2) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Sn(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Sn(2) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Sn(2) atom. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Sn(1) atom. is represented by the CIF file [CIF]
data_Sr2AlCu2SnO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.366
_cell_length_b   5.408
_cell_length_c   12.519
_cell_angle_alpha   102.410
_cell_angle_beta   102.275
_cell_angle_gamma   90.317
_symmetry_Int_Tables_number   1
_cell_volume   346.179
_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  0.660  0.641  0.720  1.0
  Sr  Sr1  1  0.382  0.353  0.282  1.0
  Sr  Sr2  1  0.158  0.135  0.719  1.0
  Sr  Sr3  1  0.886  0.865  0.281  1.0
  Al  Al4  1  0.015  0.008  0.000  1.0
  Al  Al5  1  0.511  0.492  0.001  1.0
  Cu  Cu6  1  0.069  0.558  0.887  1.0
  Cu  Cu7  1  0.966  0.450  0.108  1.0
  Cu  Cu8  1  0.567  0.050  0.892  1.0
  Cu  Cu9  1  0.465  0.941  0.114  1.0
  Sn  Sn10  1  0.733  0.291  0.501  1.0
  Sn  Sn11  1  0.246  0.733  0.501  1.0
  O  O12  1  0.858  0.653  0.501  1.0
  O  O13  1  0.354  0.356  0.501  1.0
  O  O14  1  0.738  0.726  0.897  1.0
  O  O15  1  0.648  0.272  0.104  1.0
  O  O16  1  0.241  0.877  0.897  1.0
  O  O17  1  0.147  0.131  0.104  1.0
  O  O18  1  0.389  0.372  0.894  1.0
  O  O19  1  0.292  0.619  0.108  1.0
  O  O20  1  0.889  0.227  0.893  1.0
  O  O21  1  0.795  0.774  0.107  1.0
  O  O22  1  0.697  0.139  0.666  1.0
  O  O23  1  0.362  0.848  0.325  1.0
  O  O24  1  0.184  0.671  0.677  1.0
  O  O25  1  0.864  0.304  0.336  1.0
[/CIF]
.
The compound described by Sr2Cu2AlSnO7 crystallizes in the triclinic P1 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 1-coordinate geometry to one O(2), one O(3), two equivalent O(11), and two equivalent O(13) atoms. In the second Sr site, Sr(2) is bonded in a 8-coordinate geometry to one O(2), one O(4), one O(6), one O(8), two equivalent O(12), and two equivalent O(14) atoms. In the third Sr site, Sr(3) is bonded in a 3-coordinate geometry to one O(7), two equivalent O(11), and two equivalent O(13) atoms. In the fourth Sr site, Sr(4) is bonded in a 3-coordinate geometry to one O(10), two equivalent O(12), and two equivalent O(14) atoms. There are four 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(5), one O(7), and one O(9) atom. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(10), one O(4), one O(6), and one O(8) atom. In the third Cu site, Cu(3) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), one O(7), and one O(9) atom. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(10), one O(4), one O(6), and one O(8) atom. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 1-coordinate geometry to one O(10), one O(3), one O(5), one O(6), and one O(9) atom. In the second Al site, Al(2) is bonded in a 1-coordinate geometry to one O(10), one O(3), one O(4), one O(7), and one O(8) atom. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(14), and one O(2) atom. In the second Sn site, Sn(2) is bonded in a 4-coordinate geometry to one O(1), one O(12), one O(13), and one O(2) atom. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Sn(1) and one Sn(2) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), one Sn(1), and one Sn(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Sr(1), one Cu(1), one Cu(3), one Al(1), and one Al(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one Al(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(3), one Cu(1), one Cu(3), and one Al(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Sr(2), one Cu(2), one Cu(4), and one Al(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(3), and one Al(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(4), one Cu(2), one Cu(4), one Al(1), and one Al(2) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Sn(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Sn(2) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(3), and one Sn(2) atom. In the fourteenth O site, O(14) is bonded in a 5-coordinate geometry to two equivalent Sr(2), two equivalent Sr(4), and one Sn(1) atom. is represented by the CIF file [CIF]
data_Sr2AlCu2SnO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.366
_cell_length_b   5.408
_cell_length_c   12.519
_cell_angle_alpha   102.410
_cell_angle_beta   102.275
_cell_angle_gamma   90.317
_symmetry_Int_Tables_number   1
_cell_volume   346.179
_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  0.660  0.641  0.720  1.0
  Sr  Sr1  1  0.382  0.353  0.282  1.0
  Sr  Sr2  1  0.158  0.135  0.719  1.0
  Sr  Sr3  1  0.886  0.865  0.281  1.0
  Al  Al4  1  0.015  0.008  0.000  1.0
  Al  Al5  1  0.511  0.492  0.001  1.0
  Cu  Cu6  1  0.069  0.558  0.887  1.0
  Cu  Cu7  1  0.966  0.450  0.108  1.0
  Cu  Cu8  1  0.567  0.050  0.892  1.0
  Cu  Cu9  1  0.465  0.941  0.114  1.0
  Sn  Sn10  1  0.733  0.291  0.501  1.0
  Sn  Sn11  1  0.246  0.733  0.501  1.0
  O  O12  1  0.858  0.653  0.501  1.0
  O  O13  1  0.354  0.356  0.501  1.0
  O  O14  1  0.738  0.726  0.897  1.0
  O  O15  1  0.648  0.272  0.104  1.0
  O  O16  1  0.241  0.877  0.897  1.0
  O  O17  1  0.147  0.131  0.104  1.0
  O  O18  1  0.389  0.372  0.894  1.0
  O  O19  1  0.292  0.619  0.108  1.0
  O  O20  1  0.889  0.227  0.893  1.0
  O  O21  1  0.795  0.774  0.107  1.0
  O  O22  1  0.697  0.139  0.666  1.0
  O  O23  1  0.362  0.848  0.325  1.0
  O  O24  1  0.184  0.671  0.677  1.0
  O  O25  1  0.864  0.304  0.336  1.0
[/CIF]
.