The material structure described by BaSr2I6 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/c space group. Ba(1) is bonded to two equivalent I(2) and four equivalent I(1) atoms to form distorted BaI6 pentagonal pyramids that share corners with four equivalent Sr(1)I6 octahedra, edges with two equivalent Sr(1)I6 octahedra, and edges with two equivalent Ba(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 41-58°. Sr(1) is bonded to one I(1), two equivalent I(2), and three equivalent I(3) atoms to form SrI6 octahedra that share corners with six equivalent Sr(1)I6 octahedra, corners with two equivalent Ba(1)I6 pentagonal pyramids,  an edgeedge with one Sr(1)I6 octahedra, and  an edgeedge with one Ba(1)I6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 44-62°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a distorted trigonal planar geometry to two equivalent Ba(1) and one Sr(1) atom. In the second I site, I(2) is bonded in a trigonal planar geometry to one Ba(1) and two equivalent Sr(1) atoms. In the third I site, I(3) is bonded in a distorted trigonal planar geometry to three equivalent Sr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSr2I6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.730
_cell_length_b   13.730
_cell_length_c   8.975
_cell_angle_alpha   84.800
_cell_angle_beta   84.800
_cell_angle_gamma   33.469
_symmetry_Int_Tables_number   1
_cell_volume   928.843
_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  0.734  0.266  0.250  1.0
  Ba  Ba1  1  0.266  0.734  0.750  1.0
  Sr  Sr2  1  0.054  0.603  0.135  1.0
  Sr  Sr3  1  0.603  0.054  0.635  1.0
  Sr  Sr4  1  0.397  0.946  0.365  1.0
  Sr  Sr5  1  0.946  0.397  0.865  1.0
  I  I6  1  0.368  0.497  0.077  1.0
  I  I7  1  0.497  0.368  0.577  1.0
  I  I8  1  0.908  0.880  0.376  1.0
  I  I9  1  0.880  0.908  0.876  1.0
  I  I10  1  0.327  0.240  0.359  1.0
  I  I11  1  0.240  0.327  0.859  1.0
  I  I12  1  0.760  0.673  0.141  1.0
  I  I13  1  0.673  0.760  0.641  1.0
  I  I14  1  0.120  0.092  0.124  1.0
  I  I15  1  0.092  0.120  0.624  1.0
  I  I16  1  0.503  0.632  0.423  1.0
  I  I17  1  0.632  0.503  0.923  1.0
[/CIF]
.
The material structure described by BaSr2I6 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/c space group. Ba(1) is bonded to two equivalent I(2) and four equivalent I(1) atoms to form distorted BaI6 pentagonal pyramids that share corners with four equivalent Sr(1)I6 octahedra, edges with two equivalent Sr(1)I6 octahedra, and edges with two equivalent Ba(1)I6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 41-58°. Sr(1) is bonded to one I(1), two equivalent I(2), and three equivalent I(3) atoms to form SrI6 octahedra that share corners with six equivalent Sr(1)I6 octahedra, corners with two equivalent Ba(1)I6 pentagonal pyramids,  an edgeedge with one Sr(1)I6 octahedra, and  an edgeedge with one Ba(1)I6 pentagonal pyramid. The corner-sharing octahedral tilt angles range from 44-62°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a distorted trigonal planar geometry to two equivalent Ba(1) and one Sr(1) atom. In the second I site, I(2) is bonded in a trigonal planar geometry to one Ba(1) and two equivalent Sr(1) atoms. In the third I site, I(3) is bonded in a distorted trigonal planar geometry to three equivalent Sr(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaSr2I6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.730
_cell_length_b   13.730
_cell_length_c   8.975
_cell_angle_alpha   84.800
_cell_angle_beta   84.800
_cell_angle_gamma   33.469
_symmetry_Int_Tables_number   1
_cell_volume   928.843
_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  0.734  0.266  0.250  1.0
  Ba  Ba1  1  0.266  0.734  0.750  1.0
  Sr  Sr2  1  0.054  0.603  0.135  1.0
  Sr  Sr3  1  0.603  0.054  0.635  1.0
  Sr  Sr4  1  0.397  0.946  0.365  1.0
  Sr  Sr5  1  0.946  0.397  0.865  1.0
  I  I6  1  0.368  0.497  0.077  1.0
  I  I7  1  0.497  0.368  0.577  1.0
  I  I8  1  0.908  0.880  0.376  1.0
  I  I9  1  0.880  0.908  0.876  1.0
  I  I10  1  0.327  0.240  0.359  1.0
  I  I11  1  0.240  0.327  0.859  1.0
  I  I12  1  0.760  0.673  0.141  1.0
  I  I13  1  0.673  0.760  0.641  1.0
  I  I14  1  0.120  0.092  0.124  1.0
  I  I15  1  0.092  0.120  0.624  1.0
  I  I16  1  0.503  0.632  0.423  1.0
  I  I17  1  0.632  0.503  0.923  1.0
[/CIF]
.