The material described by Sr2CaI6 is Hydrophilite-derived structured and crystallizes in the trigonal P321 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form SrI6 octahedra that share corners with four equivalent Ca(1)I6 octahedra, corners with six equivalent Sr(2)I6 octahedra, and  an edgeedge with one Ca(2)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. In the second Sr site, Sr(2) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form SrI6 octahedra that share corners with two equivalent Ca(2)I6 octahedra, corners with six equivalent Sr(1)I6 octahedra, and edges with two equivalent Ca(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-56°. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent I(2) and three equivalent I(3) atoms to form CaI6 octahedra that share corners with six equivalent Sr(1)I6 octahedra and edges with three equivalent Sr(2)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. In the second Ca site, Ca(2) is bonded to six equivalent I(1) atoms to form CaI6 octahedra that share corners with six equivalent Sr(2)I6 octahedra and edges with three equivalent Sr(1)I6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(2) atom. In the second I site, I(2) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(1) atom. In the third I site, I(3) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(1) atom. is represented by the CIF card [CIF]
data_Sr2CaI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.882
_cell_length_b   13.882
_cell_length_c   7.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   1249.190
_cell_formula_units_Z   3
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  0.000  0.643  0.000  1.0
  Sr  Sr1  1  0.000  0.310  0.500  1.0
  Sr  Sr2  1  0.357  0.357  0.000  1.0
  Sr  Sr3  1  0.310  0.000  0.500  1.0
  Sr  Sr4  1  0.690  0.690  0.500  1.0
  Sr  Sr5  1  0.643  0.000  0.000  1.0
  Ca  Ca6  1  0.333  0.667  0.496  1.0
  Ca  Ca7  1  0.000  0.000  0.000  1.0
  Ca  Ca8  1  0.667  0.333  0.504  1.0
  I  I9  1  0.090  0.875  0.762  1.0
  I  I10  1  0.228  0.775  0.253  1.0
  I  I11  1  0.122  0.540  0.742  1.0
  I  I12  1  0.419  0.878  0.742  1.0
  I  I13  1  0.225  0.453  0.253  1.0
  I  I14  1  0.125  0.215  0.762  1.0
  I  I15  1  0.547  0.772  0.253  1.0
  I  I16  1  0.215  0.125  0.238  1.0
  I  I17  1  0.460  0.581  0.742  1.0
  I  I18  1  0.785  0.910  0.762  1.0
  I  I19  1  0.453  0.225  0.747  1.0
  I  I20  1  0.581  0.460  0.258  1.0
  I  I21  1  0.540  0.122  0.258  1.0
  I  I22  1  0.772  0.547  0.747  1.0
  I  I23  1  0.910  0.785  0.238  1.0
  I  I24  1  0.775  0.228  0.747  1.0
  I  I25  1  0.878  0.419  0.258  1.0
  I  I26  1  0.875  0.090  0.238  1.0
[/CIF]
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The material described by Sr2CaI6 is Hydrophilite-derived structured and crystallizes in the trigonal P321 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form SrI6 octahedra that share corners with four equivalent Ca(1)I6 octahedra, corners with six equivalent Sr(2)I6 octahedra, and  an edgeedge with one Ca(2)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. In the second Sr site, Sr(2) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form SrI6 octahedra that share corners with two equivalent Ca(2)I6 octahedra, corners with six equivalent Sr(1)I6 octahedra, and edges with two equivalent Ca(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-56°. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to three equivalent I(2) and three equivalent I(3) atoms to form CaI6 octahedra that share corners with six equivalent Sr(1)I6 octahedra and edges with three equivalent Sr(2)I6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. In the second Ca site, Ca(2) is bonded to six equivalent I(1) atoms to form CaI6 octahedra that share corners with six equivalent Sr(2)I6 octahedra and edges with three equivalent Sr(1)I6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are three inequivalent I sites. In the first I site, I(1) is bonded in a trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(2) atom. In the second I site, I(2) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(1) atom. In the third I site, I(3) is bonded in a distorted trigonal planar geometry to one Sr(1), one Sr(2), and one Ca(1) atom. is represented by the CIF card [CIF]
data_Sr2CaI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.882
_cell_length_b   13.882
_cell_length_c   7.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   1249.190
_cell_formula_units_Z   3
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  0.000  0.643  0.000  1.0
  Sr  Sr1  1  0.000  0.310  0.500  1.0
  Sr  Sr2  1  0.357  0.357  0.000  1.0
  Sr  Sr3  1  0.310  0.000  0.500  1.0
  Sr  Sr4  1  0.690  0.690  0.500  1.0
  Sr  Sr5  1  0.643  0.000  0.000  1.0
  Ca  Ca6  1  0.333  0.667  0.496  1.0
  Ca  Ca7  1  0.000  0.000  0.000  1.0
  Ca  Ca8  1  0.667  0.333  0.504  1.0
  I  I9  1  0.090  0.875  0.762  1.0
  I  I10  1  0.228  0.775  0.253  1.0
  I  I11  1  0.122  0.540  0.742  1.0
  I  I12  1  0.419  0.878  0.742  1.0
  I  I13  1  0.225  0.453  0.253  1.0
  I  I14  1  0.125  0.215  0.762  1.0
  I  I15  1  0.547  0.772  0.253  1.0
  I  I16  1  0.215  0.125  0.238  1.0
  I  I17  1  0.460  0.581  0.742  1.0
  I  I18  1  0.785  0.910  0.762  1.0
  I  I19  1  0.453  0.225  0.747  1.0
  I  I20  1  0.581  0.460  0.258  1.0
  I  I21  1  0.540  0.122  0.258  1.0
  I  I22  1  0.772  0.547  0.747  1.0
  I  I23  1  0.910  0.785  0.238  1.0
  I  I24  1  0.775  0.228  0.747  1.0
  I  I25  1  0.878  0.419  0.258  1.0
  I  I26  1  0.875  0.090  0.238  1.0
[/CIF]
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