The material structure described by CaPbI4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded to one I(1), one I(3), one I(4), and two equivalent I(2) atoms to form distorted CaI5 trigonal bipyramids that share  a cornercorner with one Pb(1)I6 pentagonal pyramid, edges with three equivalent Pb(1)I6 pentagonal pyramids, and  an edgeedge with one Ca(1)I5 trigonal bipyramid. Pb(1) is bonded to one I(2), one I(3), two equivalent I(1), and two equivalent I(4) atoms to form distorted PbI6 pentagonal pyramids that share corners with two equivalent Pb(1)I6 pentagonal pyramids,  a cornercorner with one Ca(1)I5 trigonal bipyramid,  an edgeedge with one Pb(1)I6 pentagonal pyramid, and edges with three equivalent Ca(1)I5 trigonal bipyramids. There are four inequivalent I sites. In the first I site, I(1) is bonded in a 3-coordinate geometry to one Ca(1) and two equivalent Pb(1) atoms. In the second I site, I(2) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one Pb(1) atom. In the third I site, I(3) is bonded in a water-like geometry to one Ca(1) and one Pb(1) atom. In the fourth I site, I(4) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1) and two equivalent Pb(1) atoms. is represented by the CIF file [CIF]
data_CaPbI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.829
_cell_length_b   9.521
_cell_length_c   17.608
_cell_angle_alpha   60.662
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1144.142
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.372  0.788  0.620  1.0
  Ca  Ca1  1  0.128  0.788  0.120  1.0
  Ca  Ca2  1  0.872  0.212  0.880  1.0
  Ca  Ca3  1  0.628  0.212  0.380  1.0
  Pb  Pb4  1  0.074  0.757  0.864  1.0
  Pb  Pb5  1  0.426  0.757  0.364  1.0
  Pb  Pb6  1  0.574  0.243  0.636  1.0
  Pb  Pb7  1  0.926  0.243  0.136  1.0
  I  I8  1  0.208  0.036  0.667  1.0
  I  I9  1  0.292  0.036  0.167  1.0
  I  I10  1  0.718  0.971  0.579  1.0
  I  I11  1  0.782  0.971  0.079  1.0
  I  I12  1  0.263  0.533  0.806  1.0
  I  I13  1  0.282  0.536  0.559  1.0
  I  I14  1  0.237  0.533  0.306  1.0
  I  I15  1  0.782  0.464  0.941  1.0
  I  I16  1  0.218  0.536  0.059  1.0
  I  I17  1  0.763  0.467  0.694  1.0
  I  I18  1  0.718  0.464  0.441  1.0
  I  I19  1  0.737  0.467  0.194  1.0
  I  I20  1  0.218  0.029  0.921  1.0
  I  I21  1  0.282  0.029  0.421  1.0
  I  I22  1  0.708  0.964  0.833  1.0
  I  I23  1  0.792  0.964  0.333  1.0
[/CIF]
.
The material structure described by CaPbI4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded to one I(1), one I(3), one I(4), and two equivalent I(2) atoms to form distorted CaI5 trigonal bipyramids that share  a cornercorner with one Pb(1)I6 pentagonal pyramid, edges with three equivalent Pb(1)I6 pentagonal pyramids, and  an edgeedge with one Ca(1)I5 trigonal bipyramid. Pb(1) is bonded to one I(2), one I(3), two equivalent I(1), and two equivalent I(4) atoms to form distorted PbI6 pentagonal pyramids that share corners with two equivalent Pb(1)I6 pentagonal pyramids,  a cornercorner with one Ca(1)I5 trigonal bipyramid,  an edgeedge with one Pb(1)I6 pentagonal pyramid, and edges with three equivalent Ca(1)I5 trigonal bipyramids. There are four inequivalent I sites. In the first I site, I(1) is bonded in a 3-coordinate geometry to one Ca(1) and two equivalent Pb(1) atoms. In the second I site, I(2) is bonded in a 3-coordinate geometry to two equivalent Ca(1) and one Pb(1) atom. In the third I site, I(3) is bonded in a water-like geometry to one Ca(1) and one Pb(1) atom. In the fourth I site, I(4) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1) and two equivalent Pb(1) atoms. is represented by the CIF file [CIF]
data_CaPbI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.829
_cell_length_b   9.521
_cell_length_c   17.608
_cell_angle_alpha   60.662
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1144.142
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.372  0.788  0.620  1.0
  Ca  Ca1  1  0.128  0.788  0.120  1.0
  Ca  Ca2  1  0.872  0.212  0.880  1.0
  Ca  Ca3  1  0.628  0.212  0.380  1.0
  Pb  Pb4  1  0.074  0.757  0.864  1.0
  Pb  Pb5  1  0.426  0.757  0.364  1.0
  Pb  Pb6  1  0.574  0.243  0.636  1.0
  Pb  Pb7  1  0.926  0.243  0.136  1.0
  I  I8  1  0.208  0.036  0.667  1.0
  I  I9  1  0.292  0.036  0.167  1.0
  I  I10  1  0.718  0.971  0.579  1.0
  I  I11  1  0.782  0.971  0.079  1.0
  I  I12  1  0.263  0.533  0.806  1.0
  I  I13  1  0.282  0.536  0.559  1.0
  I  I14  1  0.237  0.533  0.306  1.0
  I  I15  1  0.782  0.464  0.941  1.0
  I  I16  1  0.218  0.536  0.059  1.0
  I  I17  1  0.763  0.467  0.694  1.0
  I  I18  1  0.718  0.464  0.441  1.0
  I  I19  1  0.737  0.467  0.194  1.0
  I  I20  1  0.218  0.029  0.921  1.0
  I  I21  1  0.282  0.029  0.421  1.0
  I  I22  1  0.708  0.964  0.833  1.0
  I  I23  1  0.792  0.964  0.333  1.0
[/CIF]
.