The crystal structure described by Ba2SrI6 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/c space group. Ba(1) is bonded to one I(1), two equivalent I(2), and three equivalent I(3) atoms to form distorted BaI6 octahedra that share corners with six equivalent Ba(1)I6 octahedra, corners with two equivalent Sr(1)I6 pentagonal pyramids,  an edgeedge with one Ba(1)I6 octahedra, and  an edgeedge with one Sr(1)I6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 53-69°. Sr(1) is bonded to two equivalent I(2) and four equivalent I(1) atoms to form distorted SrI6 pentagonal pyramids that share corners with four equivalent Ba(1)I6 octahedra, edges with two equivalent Ba(1)I6 octahedra, and edges with two equivalent Sr(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 40-61°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Ba(1) and two equivalent Sr(1) atoms. In the second I site, I(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ba(1) and one Sr(1) atom. In the third I site, I(3) is bonded in a trigonal planar geometry to three equivalent Ba(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2SrI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.826
_cell_length_b   13.826
_cell_length_c   9.103
_cell_angle_alpha   79.291
_cell_angle_beta   79.291
_cell_angle_gamma   33.887
_symmetry_Int_Tables_number   1
_cell_volume   951.632
_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
  Ba  Ba0  1  0.058  0.611  0.641  1.0
  Ba  Ba1  1  0.611  0.058  0.141  1.0
  Ba  Ba2  1  0.389  0.942  0.859  1.0
  Ba  Ba3  1  0.942  0.389  0.359  1.0
  Sr  Sr4  1  0.666  0.334  0.750  1.0
  Sr  Sr5  1  0.334  0.666  0.250  1.0
  I  I6  1  0.460  0.385  0.521  1.0
  I  I7  1  0.385  0.460  0.021  1.0
  I  I8  1  0.876  0.945  0.826  1.0
  I  I9  1  0.945  0.876  0.326  1.0
  I  I10  1  0.286  0.262  0.907  1.0
  I  I11  1  0.262  0.286  0.407  1.0
  I  I12  1  0.738  0.714  0.593  1.0
  I  I13  1  0.714  0.738  0.093  1.0
  I  I14  1  0.055  0.124  0.674  1.0
  I  I15  1  0.124  0.055  0.174  1.0
  I  I16  1  0.615  0.540  0.979  1.0
  I  I17  1  0.540  0.615  0.479  1.0
[/CIF]
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The crystal structure described by Ba2SrI6 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/c space group. Ba(1) is bonded to one I(1), two equivalent I(2), and three equivalent I(3) atoms to form distorted BaI6 octahedra that share corners with six equivalent Ba(1)I6 octahedra, corners with two equivalent Sr(1)I6 pentagonal pyramids,  an edgeedge with one Ba(1)I6 octahedra, and  an edgeedge with one Sr(1)I6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 53-69°. Sr(1) is bonded to two equivalent I(2) and four equivalent I(1) atoms to form distorted SrI6 pentagonal pyramids that share corners with four equivalent Ba(1)I6 octahedra, edges with two equivalent Ba(1)I6 octahedra, and edges with two equivalent Sr(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 40-61°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a trigonal non-coplanar geometry to one Ba(1) and two equivalent Sr(1) atoms. In the second I site, I(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ba(1) and one Sr(1) atom. In the third I site, I(3) is bonded in a trigonal planar geometry to three equivalent Ba(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2SrI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.826
_cell_length_b   13.826
_cell_length_c   9.103
_cell_angle_alpha   79.291
_cell_angle_beta   79.291
_cell_angle_gamma   33.887
_symmetry_Int_Tables_number   1
_cell_volume   951.632
_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
  Ba  Ba0  1  0.058  0.611  0.641  1.0
  Ba  Ba1  1  0.611  0.058  0.141  1.0
  Ba  Ba2  1  0.389  0.942  0.859  1.0
  Ba  Ba3  1  0.942  0.389  0.359  1.0
  Sr  Sr4  1  0.666  0.334  0.750  1.0
  Sr  Sr5  1  0.334  0.666  0.250  1.0
  I  I6  1  0.460  0.385  0.521  1.0
  I  I7  1  0.385  0.460  0.021  1.0
  I  I8  1  0.876  0.945  0.826  1.0
  I  I9  1  0.945  0.876  0.326  1.0
  I  I10  1  0.286  0.262  0.907  1.0
  I  I11  1  0.262  0.286  0.407  1.0
  I  I12  1  0.738  0.714  0.593  1.0
  I  I13  1  0.714  0.738  0.093  1.0
  I  I14  1  0.055  0.124  0.674  1.0
  I  I15  1  0.124  0.055  0.174  1.0
  I  I16  1  0.615  0.540  0.979  1.0
  I  I17  1  0.540  0.615  0.479  1.0
[/CIF]
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