The material described by Ba2Ca7I18 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 7-coordinate geometry to one I(1), one I(2), one I(3), one I(6), one I(8), and two equivalent I(9) atoms. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one I(1), one I(2), one I(4), one I(6), one I(8), and one I(9) atom to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 50-62°. In the second Ca site, Ca(2) is bonded to two equivalent I(3), two equivalent I(4), and two equivalent I(9) atoms to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 57-60°. In the third Ca site, Ca(3) is bonded to one I(1), one I(2), one I(3), one I(5), one I(7), and one I(8) atom to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. In the fourth Ca site, Ca(4) is bonded to one I(4), one I(6), one I(7), one I(8), and two equivalent I(5) atoms to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 50-62°. There are nine inequivalent I sites. In the first I site, I(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ca(1), and one Ca(3) atom. In the second I site, I(2) is bonded in a trigonal non-coplanar geometry to one Ba(1), one Ca(1), and one Ca(3) atom. In the third I site, I(3) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ca(2), and one Ca(3) atom. In the fourth I site, I(4) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one Ca(4) atom. In the fifth I site, I(5) is bonded in a distorted T-shaped geometry to one Ca(3) and two equivalent Ca(4) atoms. In the sixth I site, I(6) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ca(1), and one Ca(4) atom. In the seventh I site, I(7) is bonded in an L-shaped geometry to one Ca(3) and one Ca(4) atom. In the eighth I site, I(8) is bonded in a 3-coordinate geometry to one Ba(1), one Ca(1), one Ca(3), and one Ca(4) atom. In the ninth I site, I(9) is bonded to two equivalent Ba(1), one Ca(1), and one Ca(2) atom to form a mixture of distorted corner and edge-sharing IBa2Ca2 trigonal pyramids. is represented by the CIF file [CIF]
data_Ba2Ca7I18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.372
_cell_length_b   11.215
_cell_length_c   11.482
_cell_angle_alpha   95.690
_cell_angle_beta   115.891
_cell_angle_gamma   94.905
_symmetry_Int_Tables_number   1
_cell_volume   1183.167
_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
  Ba  Ba0  1  0.692  0.390  0.232  1.0
  Ba  Ba1  1  0.308  0.610  0.768  1.0
  Ca  Ca2  1  0.795  0.818  0.117  1.0
  Ca  Ca3  1  0.000  0.500  0.000  1.0
  Ca  Ca4  1  0.799  0.789  0.611  1.0
  Ca  Ca5  1  0.594  0.113  0.703  1.0
  Ca  Ca6  1  0.406  0.887  0.297  1.0
  Ca  Ca7  1  0.201  0.211  0.389  1.0
  Ca  Ca8  1  0.205  0.182  0.883  1.0
  I  I9  1  0.879  0.087  0.242  1.0
  I  I10  1  0.863  0.698  0.371  1.0
  I  I11  1  0.940  0.561  0.720  1.0
  I  I12  1  0.918  0.222  0.898  1.0
  I  I13  1  0.708  0.029  0.501  1.0
  I  I14  1  0.475  0.818  0.060  1.0
  I  I15  1  0.489  0.659  0.426  1.0
  I  I16  1  0.662  0.857  0.809  1.0
  I  I17  1  0.314  0.459  0.030  1.0
  I  I18  1  0.686  0.541  0.970  1.0
  I  I19  1  0.338  0.143  0.191  1.0
  I  I20  1  0.511  0.341  0.574  1.0
  I  I21  1  0.525  0.182  0.940  1.0
  I  I22  1  0.292  0.971  0.499  1.0
  I  I23  1  0.082  0.778  0.102  1.0
  I  I24  1  0.060  0.439  0.280  1.0
  I  I25  1  0.137  0.302  0.629  1.0
  I  I26  1  0.121  0.913  0.758  1.0
[/CIF]
.
The material described by Ba2Ca7I18 crystallizes in the triclinic P-1 space group. Ba(1) is bonded in a 7-coordinate geometry to one I(1), one I(2), one I(3), one I(6), one I(8), and two equivalent I(9) atoms. There are four inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one I(1), one I(2), one I(4), one I(6), one I(8), and one I(9) atom to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 50-62°. In the second Ca site, Ca(2) is bonded to two equivalent I(3), two equivalent I(4), and two equivalent I(9) atoms to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 57-60°. In the third Ca site, Ca(3) is bonded to one I(1), one I(2), one I(3), one I(5), one I(7), and one I(8) atom to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. In the fourth Ca site, Ca(4) is bonded to one I(4), one I(6), one I(7), one I(8), and two equivalent I(5) atoms to form a mixture of corner and edge-sharing CaI6 octahedra. The corner-sharing octahedral tilt angles range from 50-62°. There are nine inequivalent I sites. In the first I site, I(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ca(1), and one Ca(3) atom. In the second I site, I(2) is bonded in a trigonal non-coplanar geometry to one Ba(1), one Ca(1), and one Ca(3) atom. In the third I site, I(3) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1), one Ca(2), and one Ca(3) atom. In the fourth I site, I(4) is bonded in a trigonal planar geometry to one Ca(1), one Ca(2), and one Ca(4) atom. In the fifth I site, I(5) is bonded in a distorted T-shaped geometry to one Ca(3) and two equivalent Ca(4) atoms. In the sixth I site, I(6) is bonded in a distorted trigonal planar geometry to one Ba(1), one Ca(1), and one Ca(4) atom. In the seventh I site, I(7) is bonded in an L-shaped geometry to one Ca(3) and one Ca(4) atom. In the eighth I site, I(8) is bonded in a 3-coordinate geometry to one Ba(1), one Ca(1), one Ca(3), and one Ca(4) atom. In the ninth I site, I(9) is bonded to two equivalent Ba(1), one Ca(1), and one Ca(2) atom to form a mixture of distorted corner and edge-sharing IBa2Ca2 trigonal pyramids. is represented by the CIF file [CIF]
data_Ba2Ca7I18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.372
_cell_length_b   11.215
_cell_length_c   11.482
_cell_angle_alpha   95.690
_cell_angle_beta   115.891
_cell_angle_gamma   94.905
_symmetry_Int_Tables_number   1
_cell_volume   1183.167
_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
  Ba  Ba0  1  0.692  0.390  0.232  1.0
  Ba  Ba1  1  0.308  0.610  0.768  1.0
  Ca  Ca2  1  0.795  0.818  0.117  1.0
  Ca  Ca3  1  0.000  0.500  0.000  1.0
  Ca  Ca4  1  0.799  0.789  0.611  1.0
  Ca  Ca5  1  0.594  0.113  0.703  1.0
  Ca  Ca6  1  0.406  0.887  0.297  1.0
  Ca  Ca7  1  0.201  0.211  0.389  1.0
  Ca  Ca8  1  0.205  0.182  0.883  1.0
  I  I9  1  0.879  0.087  0.242  1.0
  I  I10  1  0.863  0.698  0.371  1.0
  I  I11  1  0.940  0.561  0.720  1.0
  I  I12  1  0.918  0.222  0.898  1.0
  I  I13  1  0.708  0.029  0.501  1.0
  I  I14  1  0.475  0.818  0.060  1.0
  I  I15  1  0.489  0.659  0.426  1.0
  I  I16  1  0.662  0.857  0.809  1.0
  I  I17  1  0.314  0.459  0.030  1.0
  I  I18  1  0.686  0.541  0.970  1.0
  I  I19  1  0.338  0.143  0.191  1.0
  I  I20  1  0.511  0.341  0.574  1.0
  I  I21  1  0.525  0.182  0.940  1.0
  I  I22  1  0.292  0.971  0.499  1.0
  I  I23  1  0.082  0.778  0.102  1.0
  I  I24  1  0.060  0.439  0.280  1.0
  I  I25  1  0.137  0.302  0.629  1.0
  I  I26  1  0.121  0.913  0.758  1.0
[/CIF]
.