The crystal structure described by Sr2Cu3O4Br2 crystallizes in the tetragonal I4/mmm space group. Sr(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent Br(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded to two equivalent Sr(1), one Cu(2), and two equivalent Cu(1) atoms to form OSr2Cu3 trigonal bipyramids that share corners with eight equivalent Br(1)Sr4 tetrahedra, corners with three equivalent O(1)Sr2Cu3 trigonal bipyramids, edges with three equivalent O(1)Sr2Cu3 trigonal bipyramids, and faces with two equivalent O(1)Sr2Cu3 trigonal bipyramids. Br(1) is bonded to four equivalent Sr(1) atoms to form BrSr4 tetrahedra that share corners with four equivalent Br(1)Sr4 tetrahedra, corners with sixteen equivalent O(1)Sr2Cu3 trigonal bipyramids, and edges with four equivalent Br(1)Sr4 tetrahedra. is represented by the CIF file [CIF]
data_Sr2Cu3(BrO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.519
_cell_length_b   5.519
_cell_length_c   7.883
_cell_angle_alpha   110.491
_cell_angle_beta   110.491
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   208.602
_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  0.369  0.369  0.739  1.0
  Sr  Sr1  1  0.631  0.631  0.261  1.0
  Cu  Cu2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Cu  Cu4  1  0.500  0.000  0.000  1.0
  Br  Br5  1  0.250  0.750  0.500  1.0
  Br  Br6  1  0.750  0.250  0.500  1.0
  O  O7  1  0.750  0.750  0.000  1.0
  O  O8  1  0.250  0.250  1.000  1.0
  O  O9  1  0.750  0.250  0.000  1.0
  O  O10  1  0.250  0.750  0.000  1.0
[/CIF]
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The crystal structure described by Sr2Cu3O4Br2 crystallizes in the tetragonal I4/mmm space group. Sr(1) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent Br(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to four equivalent O(1) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to four equivalent O(1) atoms. O(1) is bonded to two equivalent Sr(1), one Cu(2), and two equivalent Cu(1) atoms to form OSr2Cu3 trigonal bipyramids that share corners with eight equivalent Br(1)Sr4 tetrahedra, corners with three equivalent O(1)Sr2Cu3 trigonal bipyramids, edges with three equivalent O(1)Sr2Cu3 trigonal bipyramids, and faces with two equivalent O(1)Sr2Cu3 trigonal bipyramids. Br(1) is bonded to four equivalent Sr(1) atoms to form BrSr4 tetrahedra that share corners with four equivalent Br(1)Sr4 tetrahedra, corners with sixteen equivalent O(1)Sr2Cu3 trigonal bipyramids, and edges with four equivalent Br(1)Sr4 tetrahedra. is represented by the CIF file [CIF]
data_Sr2Cu3(BrO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.519
_cell_length_b   5.519
_cell_length_c   7.883
_cell_angle_alpha   110.491
_cell_angle_beta   110.491
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   208.602
_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  0.369  0.369  0.739  1.0
  Sr  Sr1  1  0.631  0.631  0.261  1.0
  Cu  Cu2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Cu  Cu4  1  0.500  0.000  0.000  1.0
  Br  Br5  1  0.250  0.750  0.500  1.0
  Br  Br6  1  0.750  0.250  0.500  1.0
  O  O7  1  0.750  0.750  0.000  1.0
  O  O8  1  0.250  0.250  1.000  1.0
  O  O9  1  0.750  0.250  0.000  1.0
  O  O10  1  0.250  0.750  0.000  1.0
[/CIF]
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