The compound described by Sr3CaI8 is Fluorite-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. In the second Sr site, Sr(2) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. I(1) is bonded to one Sr(2), two equivalent Sr(1), and one Ca(1) atom to form a mixture of corner and edge-sharing ISr3Ca tetrahedra. is represented by the CIF file [CIF]
data_Sr3CaI8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.807
_cell_length_b   9.807
_cell_length_c   9.807
_cell_angle_alpha   131.791
_cell_angle_beta   131.791
_cell_angle_gamma   70.559
_symmetry_Int_Tables_number   1
_cell_volume   513.656
_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
  Sr  Sr0  1  0.750  0.250  0.500  1.0
  Sr  Sr1  1  0.500  0.500  0.000  1.0
  Sr  Sr2  1  0.250  0.750  0.500  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  I  I4  1  0.630  0.123  0.000  1.0
  I  I5  1  0.123  0.123  0.493  1.0
  I  I6  1  0.877  0.370  0.000  1.0
  I  I7  1  0.370  0.370  0.493  1.0
  I  I8  1  0.123  0.630  0.000  1.0
  I  I9  1  0.630  0.630  0.507  1.0
  I  I10  1  0.370  0.877  0.000  1.0
  I  I11  1  0.877  0.877  0.507  1.0
[/CIF]
.
The compound described by Sr3CaI8 is Fluorite-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. In the second Sr site, Sr(2) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent I(1) atoms. I(1) is bonded to one Sr(2), two equivalent Sr(1), and one Ca(1) atom to form a mixture of corner and edge-sharing ISr3Ca tetrahedra. is represented by the CIF file [CIF]
data_Sr3CaI8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.807
_cell_length_b   9.807
_cell_length_c   9.807
_cell_angle_alpha   131.791
_cell_angle_beta   131.791
_cell_angle_gamma   70.559
_symmetry_Int_Tables_number   1
_cell_volume   513.656
_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
  Sr  Sr0  1  0.750  0.250  0.500  1.0
  Sr  Sr1  1  0.500  0.500  0.000  1.0
  Sr  Sr2  1  0.250  0.750  0.500  1.0
  Ca  Ca3  1  0.000  0.000  0.000  1.0
  I  I4  1  0.630  0.123  0.000  1.0
  I  I5  1  0.123  0.123  0.493  1.0
  I  I6  1  0.877  0.370  0.000  1.0
  I  I7  1  0.370  0.370  0.493  1.0
  I  I8  1  0.123  0.630  0.000  1.0
  I  I9  1  0.630  0.630  0.507  1.0
  I  I10  1  0.370  0.877  0.000  1.0
  I  I11  1  0.877  0.877  0.507  1.0
[/CIF]
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