The material described by Sr2CaI6 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted edge-sharing SrI6 pentagonal pyramids. Ca(1) is bonded in a 8-coordinate geometry to two equivalent I(1), two equivalent I(2), and four equivalent I(3) atoms. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the second I site, I(2) is bonded in a distorted T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the third I site, I(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1) and two equivalent Ca(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2CaI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.861
_cell_length_b   8.861
_cell_length_c   11.516
_cell_angle_alpha   86.569
_cell_angle_beta   86.569
_cell_angle_gamma   121.652
_symmetry_Int_Tables_number   1
_cell_volume   763.800
_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
  Sr  Sr0  1  0.299  0.618  0.541  1.0
  Sr  Sr1  1  0.382  0.701  0.959  1.0
  Sr  Sr2  1  0.618  0.299  0.041  1.0
  Sr  Sr3  1  0.701  0.382  0.459  1.0
  Ca  Ca4  1  0.046  0.954  0.250  1.0
  Ca  Ca5  1  0.954  0.046  0.750  1.0
  I  I6  1  0.295  0.364  0.144  1.0
  I  I7  1  0.953  0.560  0.196  1.0
  I  I8  1  0.025  0.771  0.539  1.0
  I  I9  1  0.229  0.975  0.961  1.0
  I  I10  1  0.440  0.047  0.304  1.0
  I  I11  1  0.636  0.705  0.356  1.0
  I  I12  1  0.364  0.295  0.644  1.0
  I  I13  1  0.560  0.953  0.696  1.0
  I  I14  1  0.771  0.025  0.039  1.0
  I  I15  1  0.975  0.229  0.461  1.0
  I  I16  1  0.047  0.440  0.804  1.0
  I  I17  1  0.705  0.636  0.856  1.0
[/CIF]
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The material described by Sr2CaI6 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded to two equivalent I(1), two equivalent I(2), and two equivalent I(3) atoms to form distorted edge-sharing SrI6 pentagonal pyramids. Ca(1) is bonded in a 8-coordinate geometry to two equivalent I(1), two equivalent I(2), and four equivalent I(3) atoms. There are three inequivalent I sites. In the first I site, I(1) is bonded in a T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the second I site, I(2) is bonded in a distorted T-shaped geometry to two equivalent Sr(1) and one Ca(1) atom. In the third I site, I(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr(1) and two equivalent Ca(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2CaI6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.861
_cell_length_b   8.861
_cell_length_c   11.516
_cell_angle_alpha   86.569
_cell_angle_beta   86.569
_cell_angle_gamma   121.652
_symmetry_Int_Tables_number   1
_cell_volume   763.800
_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
  Sr  Sr0  1  0.299  0.618  0.541  1.0
  Sr  Sr1  1  0.382  0.701  0.959  1.0
  Sr  Sr2  1  0.618  0.299  0.041  1.0
  Sr  Sr3  1  0.701  0.382  0.459  1.0
  Ca  Ca4  1  0.046  0.954  0.250  1.0
  Ca  Ca5  1  0.954  0.046  0.750  1.0
  I  I6  1  0.295  0.364  0.144  1.0
  I  I7  1  0.953  0.560  0.196  1.0
  I  I8  1  0.025  0.771  0.539  1.0
  I  I9  1  0.229  0.975  0.961  1.0
  I  I10  1  0.440  0.047  0.304  1.0
  I  I11  1  0.636  0.705  0.356  1.0
  I  I12  1  0.364  0.295  0.644  1.0
  I  I13  1  0.560  0.953  0.696  1.0
  I  I14  1  0.771  0.025  0.039  1.0
  I  I15  1  0.975  0.229  0.461  1.0
  I  I16  1  0.047  0.440  0.804  1.0
  I  I17  1  0.705  0.636  0.856  1.0
[/CIF]
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