The material structure described by Sr3CaI8 is Fluorite-derived structured and crystallizes in the monoclinic Cm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. In the second Sr site, Sr(2) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. Ca(1) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. There are six inequivalent I sites. In the first I site, 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. In the second I site, I(2) 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. In the third I site, I(3) 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. In the fourth I site, I(4) 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. In the fifth I site, I(5) 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. In the sixth I site, I(6) 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 card [CIF]
data_Sr3CaI8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.997
_cell_length_b   7.997
_cell_length_c   9.771
_cell_angle_alpha   113.929
_cell_angle_beta   113.929
_cell_angle_gamma   90.186
_symmetry_Int_Tables_number   1
_cell_volume   511.475
_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  0.250  0.753  0.498  1.0
  Sr  Sr1  1  0.502  0.502  0.000  1.0
  Sr  Sr2  1  0.753  0.250  0.498  1.0
  Ca  Ca3  1  0.001  0.001  0.000  1.0
  I  I4  1  0.124  0.124  0.750  1.0
  I  I5  1  0.127  0.635  0.755  1.0
  I  I6  1  0.370  0.370  0.246  1.0
  I  I7  1  0.375  0.881  0.247  1.0
  I  I8  1  0.629  0.629  0.751  1.0
  I  I9  1  0.635  0.127  0.755  1.0
  I  I10  1  0.880  0.880  0.243  1.0
  I  I11  1  0.881  0.375  0.247  1.0
[/CIF]
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The material structure described by Sr3CaI8 is Fluorite-derived structured and crystallizes in the monoclinic Cm space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. In the second Sr site, Sr(2) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. Ca(1) is bonded in a body-centered cubic geometry to one I(1), one I(3), one I(5), one I(6), two equivalent I(2), and two equivalent I(4) atoms. There are six inequivalent I sites. In the first I site, 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. In the second I site, I(2) 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. In the third I site, I(3) 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. In the fourth I site, I(4) 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. In the fifth I site, I(5) 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. In the sixth I site, I(6) 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 card [CIF]
data_Sr3CaI8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.997
_cell_length_b   7.997
_cell_length_c   9.771
_cell_angle_alpha   113.929
_cell_angle_beta   113.929
_cell_angle_gamma   90.186
_symmetry_Int_Tables_number   1
_cell_volume   511.475
_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  0.250  0.753  0.498  1.0
  Sr  Sr1  1  0.502  0.502  0.000  1.0
  Sr  Sr2  1  0.753  0.250  0.498  1.0
  Ca  Ca3  1  0.001  0.001  0.000  1.0
  I  I4  1  0.124  0.124  0.750  1.0
  I  I5  1  0.127  0.635  0.755  1.0
  I  I6  1  0.370  0.370  0.246  1.0
  I  I7  1  0.375  0.881  0.247  1.0
  I  I8  1  0.629  0.629  0.751  1.0
  I  I9  1  0.635  0.127  0.755  1.0
  I  I10  1  0.880  0.880  0.243  1.0
  I  I11  1  0.881  0.375  0.247  1.0
[/CIF]
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