The crystal structure described by Ba3Sr4O7 is Caswellsilverite-like structured and crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form BaO6 octahedra that share corners with two equivalent Ba(1)O6 octahedra, corners with two equivalent Ba(2)O6 octahedra, corners with two equivalent Sr(1)O6 octahedra,  an edgeedge with one Ba(2)O6 octahedra, edges with two equivalent Ba(1)O6 octahedra, edges with four equivalent Sr(2)O6 octahedra, and edges with five equivalent Sr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-6°. In the second Ba site, Ba(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form BaO6 octahedra that share corners with two equivalent Ba(2)O6 octahedra, corners with four equivalent Ba(1)O6 octahedra, edges with two equivalent Ba(1)O6 octahedra, edges with two equivalent Ba(2)O6 octahedra, and edges with eight equivalent Sr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form SrO6 octahedra that share corners with two equivalent Ba(1)O6 octahedra, corners with two equivalent Sr(1)O6 octahedra, corners with two equivalent Sr(2)O6 octahedra,  an edgeedge with one Sr(2)O6 octahedra, edges with five equivalent Ba(1)O6 octahedra, and edges with six equivalent Sr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the second Sr site, Sr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form SrO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra, corners with four equivalent Sr(2)O6 octahedra,  an edgeedge with one Sr(1)O6 octahedra, edges with three equivalent Sr(2)O6 octahedra, edges with four equivalent Ba(1)O6 octahedra, and edges with four equivalent Ba(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Sr(1), and two equivalent Sr(2) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(1)Ba2Sr4 octahedra, corners with two equivalent O(2)Ba2Sr4 octahedra, corners with two equivalent O(3)Ba2Sr4 octahedra,  an edgeedge with one O(2)Ba2Sr4 octahedra, edges with two equivalent O(1)Ba2Sr4 octahedra, edges with four equivalent O(4)Ba4Sr2 octahedra, and edges with five equivalent O(3)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the second O site, O(2) is bonded to two equivalent Ba(2) and four equivalent Sr(2) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(2)Ba2Sr4 octahedra, corners with four equivalent O(1)Ba2Sr4 octahedra, edges with two equivalent O(1)Ba2Sr4 octahedra, edges with two equivalent O(2)Ba2Sr4 octahedra, and edges with eight equivalent O(4)Ba4Sr2 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Sr(1) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(1)Ba2Sr4 octahedra, corners with two equivalent O(3)Ba2Sr4 octahedra, corners with two equivalent O(4)Ba4Sr2 octahedra,  an edgeedge with one O(4)Ba4Sr2 octahedra, edges with five equivalent O(1)Ba2Sr4 octahedra, and edges with six equivalent O(3)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the fourth O site, O(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sr(2) atoms to form OBa4Sr2 octahedra that share corners with two equivalent O(3)Ba2Sr4 octahedra, corners with four equivalent O(4)Ba4Sr2 octahedra,  an edgeedge with one O(3)Ba2Sr4 octahedra, edges with three equivalent O(4)Ba4Sr2 octahedra, edges with four equivalent O(1)Ba2Sr4 octahedra, and edges with four equivalent O(2)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the CIF card [CIF]
data_Ba3Sr4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.770
_cell_length_b   13.770
_cell_length_c   13.770
_cell_angle_alpha   164.120
_cell_angle_beta   157.390
_cell_angle_gamma   27.751
_symmetry_Int_Tables_number   1
_cell_volume   274.559
_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
  Ba  Ba0  1  0.855  0.355  0.500  1.0
  Ba  Ba1  1  0.145  0.645  0.500  1.0
  Ba  Ba2  1  0.000  0.500  0.500  1.0
  Sr  Sr3  1  0.285  0.785  0.500  1.0
  Sr  Sr4  1  0.715  0.215  0.500  1.0
  Sr  Sr5  1  0.428  0.928  0.500  1.0
  Sr  Sr6  1  0.572  0.072  0.500  1.0
  O  O7  1  0.640  0.640  0.000  1.0
  O  O8  1  0.360  0.360  0.000  1.0
  O  O9  1  0.500  0.500  0.000  1.0
  O  O10  1  0.222  0.222  0.000  1.0
  O  O11  1  0.778  0.778  0.000  1.0
  O  O12  1  0.074  0.074  0.000  1.0
  O  O13  1  0.926  0.926  0.000  1.0
[/CIF]
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The crystal structure described by Ba3Sr4O7 is Caswellsilverite-like structured and crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form BaO6 octahedra that share corners with two equivalent Ba(1)O6 octahedra, corners with two equivalent Ba(2)O6 octahedra, corners with two equivalent Sr(1)O6 octahedra,  an edgeedge with one Ba(2)O6 octahedra, edges with two equivalent Ba(1)O6 octahedra, edges with four equivalent Sr(2)O6 octahedra, and edges with five equivalent Sr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-6°. In the second Ba site, Ba(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form BaO6 octahedra that share corners with two equivalent Ba(2)O6 octahedra, corners with four equivalent Ba(1)O6 octahedra, edges with two equivalent Ba(1)O6 octahedra, edges with two equivalent Ba(2)O6 octahedra, and edges with eight equivalent Sr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form SrO6 octahedra that share corners with two equivalent Ba(1)O6 octahedra, corners with two equivalent Sr(1)O6 octahedra, corners with two equivalent Sr(2)O6 octahedra,  an edgeedge with one Sr(2)O6 octahedra, edges with five equivalent Ba(1)O6 octahedra, and edges with six equivalent Sr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the second Sr site, Sr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form SrO6 octahedra that share corners with two equivalent Sr(1)O6 octahedra, corners with four equivalent Sr(2)O6 octahedra,  an edgeedge with one Sr(1)O6 octahedra, edges with three equivalent Sr(2)O6 octahedra, edges with four equivalent Ba(1)O6 octahedra, and edges with four equivalent Ba(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Sr(1), and two equivalent Sr(2) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(1)Ba2Sr4 octahedra, corners with two equivalent O(2)Ba2Sr4 octahedra, corners with two equivalent O(3)Ba2Sr4 octahedra,  an edgeedge with one O(2)Ba2Sr4 octahedra, edges with two equivalent O(1)Ba2Sr4 octahedra, edges with four equivalent O(4)Ba4Sr2 octahedra, and edges with five equivalent O(3)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the second O site, O(2) is bonded to two equivalent Ba(2) and four equivalent Sr(2) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(2)Ba2Sr4 octahedra, corners with four equivalent O(1)Ba2Sr4 octahedra, edges with two equivalent O(1)Ba2Sr4 octahedra, edges with two equivalent O(2)Ba2Sr4 octahedra, and edges with eight equivalent O(4)Ba4Sr2 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Sr(1) atoms to form OBa2Sr4 octahedra that share corners with two equivalent O(1)Ba2Sr4 octahedra, corners with two equivalent O(3)Ba2Sr4 octahedra, corners with two equivalent O(4)Ba4Sr2 octahedra,  an edgeedge with one O(4)Ba4Sr2 octahedra, edges with five equivalent O(1)Ba2Sr4 octahedra, and edges with six equivalent O(3)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the fourth O site, O(4) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sr(2) atoms to form OBa4Sr2 octahedra that share corners with two equivalent O(3)Ba2Sr4 octahedra, corners with four equivalent O(4)Ba4Sr2 octahedra,  an edgeedge with one O(3)Ba2Sr4 octahedra, edges with three equivalent O(4)Ba4Sr2 octahedra, edges with four equivalent O(1)Ba2Sr4 octahedra, and edges with four equivalent O(2)Ba2Sr4 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the CIF card [CIF]
data_Ba3Sr4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.770
_cell_length_b   13.770
_cell_length_c   13.770
_cell_angle_alpha   164.120
_cell_angle_beta   157.390
_cell_angle_gamma   27.751
_symmetry_Int_Tables_number   1
_cell_volume   274.559
_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
  Ba  Ba0  1  0.855  0.355  0.500  1.0
  Ba  Ba1  1  0.145  0.645  0.500  1.0
  Ba  Ba2  1  0.000  0.500  0.500  1.0
  Sr  Sr3  1  0.285  0.785  0.500  1.0
  Sr  Sr4  1  0.715  0.215  0.500  1.0
  Sr  Sr5  1  0.428  0.928  0.500  1.0
  Sr  Sr6  1  0.572  0.072  0.500  1.0
  O  O7  1  0.640  0.640  0.000  1.0
  O  O8  1  0.360  0.360  0.000  1.0
  O  O9  1  0.500  0.500  0.000  1.0
  O  O10  1  0.222  0.222  0.000  1.0
  O  O11  1  0.778  0.778  0.000  1.0
  O  O12  1  0.074  0.074  0.000  1.0
  O  O13  1  0.926  0.926  0.000  1.0
[/CIF]
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