The compound described by CaPbI4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded to one I(1), one I(2), one I(3), and one I(4) atom to form CaI4 tetrahedra that share corners with two equivalent Pb(1)I6 octahedra and edges with two equivalent Pb(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 61-67°. Pb(1) is bonded to one I(3), one I(4), two equivalent I(1), and two equivalent I(2) atoms to form PbI6 octahedra that share corners with two equivalent Pb(1)I6 octahedra, corners with two equivalent Ca(1)I4 tetrahedra,  an edgeedge with one Pb(1)I6 octahedra, and edges with two equivalent Ca(1)I4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. 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 one Ca(1) and two equivalent Pb(1) atoms. In the third I site, I(3) is bonded in an L-shaped geometry to one Ca(1) and one Pb(1) atom. In the fourth I site, I(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one Pb(1) atom. is represented by the CIF file [CIF]
data_CaPbI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.911
_cell_length_b   9.356
_cell_length_c   16.331
_cell_angle_alpha   87.859
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1207.893
_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  0.817  0.686  0.607  1.0
  Ca  Ca1  1  0.683  0.686  0.107  1.0
  Ca  Ca2  1  0.317  0.314  0.893  1.0
  Ca  Ca3  1  0.183  0.314  0.393  1.0
  Pb  Pb4  1  0.506  0.857  0.872  1.0
  Pb  Pb5  1  0.994  0.857  0.372  1.0
  Pb  Pb6  1  0.006  0.143  0.628  1.0
  Pb  Pb7  1  0.494  0.143  0.128  1.0
  I  I8  1  0.666  0.941  0.689  1.0
  I  I9  1  0.834  0.941  0.189  1.0
  I  I10  1  0.152  0.824  0.556  1.0
  I  I11  1  0.348  0.824  0.056  1.0
  I  I12  1  0.820  0.681  0.936  1.0
  I  I13  1  0.680  0.681  0.436  1.0
  I  I14  1  0.320  0.594  0.798  1.0
  I  I15  1  0.180  0.594  0.298  1.0
  I  I16  1  0.820  0.406  0.702  1.0
  I  I17  1  0.680  0.406  0.202  1.0
  I  I18  1  0.320  0.319  0.564  1.0
  I  I19  1  0.180  0.319  0.064  1.0
  I  I20  1  0.652  0.176  0.944  1.0
  I  I21  1  0.848  0.176  0.444  1.0
  I  I22  1  0.166  0.059  0.811  1.0
  I  I23  1  0.334  0.059  0.311  1.0
[/CIF]
.
The compound described by CaPbI4 crystallizes in the monoclinic P2_1/c space group. Ca(1) is bonded to one I(1), one I(2), one I(3), and one I(4) atom to form CaI4 tetrahedra that share corners with two equivalent Pb(1)I6 octahedra and edges with two equivalent Pb(1)I6 octahedra. The corner-sharing octahedral tilt angles range from 61-67°. Pb(1) is bonded to one I(3), one I(4), two equivalent I(1), and two equivalent I(2) atoms to form PbI6 octahedra that share corners with two equivalent Pb(1)I6 octahedra, corners with two equivalent Ca(1)I4 tetrahedra,  an edgeedge with one Pb(1)I6 octahedra, and edges with two equivalent Ca(1)I4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. 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 one Ca(1) and two equivalent Pb(1) atoms. In the third I site, I(3) is bonded in an L-shaped geometry to one Ca(1) and one Pb(1) atom. In the fourth I site, I(4) is bonded in a bent 120 degrees geometry to one Ca(1) and one Pb(1) atom. is represented by the CIF file [CIF]
data_CaPbI4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.911
_cell_length_b   9.356
_cell_length_c   16.331
_cell_angle_alpha   87.859
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   1207.893
_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  0.817  0.686  0.607  1.0
  Ca  Ca1  1  0.683  0.686  0.107  1.0
  Ca  Ca2  1  0.317  0.314  0.893  1.0
  Ca  Ca3  1  0.183  0.314  0.393  1.0
  Pb  Pb4  1  0.506  0.857  0.872  1.0
  Pb  Pb5  1  0.994  0.857  0.372  1.0
  Pb  Pb6  1  0.006  0.143  0.628  1.0
  Pb  Pb7  1  0.494  0.143  0.128  1.0
  I  I8  1  0.666  0.941  0.689  1.0
  I  I9  1  0.834  0.941  0.189  1.0
  I  I10  1  0.152  0.824  0.556  1.0
  I  I11  1  0.348  0.824  0.056  1.0
  I  I12  1  0.820  0.681  0.936  1.0
  I  I13  1  0.680  0.681  0.436  1.0
  I  I14  1  0.320  0.594  0.798  1.0
  I  I15  1  0.180  0.594  0.298  1.0
  I  I16  1  0.820  0.406  0.702  1.0
  I  I17  1  0.680  0.406  0.202  1.0
  I  I18  1  0.320  0.319  0.564  1.0
  I  I19  1  0.180  0.319  0.064  1.0
  I  I20  1  0.652  0.176  0.944  1.0
  I  I21  1  0.848  0.176  0.444  1.0
  I  I22  1  0.166  0.059  0.811  1.0
  I  I23  1  0.334  0.059  0.311  1.0
[/CIF]
.