data_CsPb3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.14
_cell_length_b   6.14
_cell_length_c   6.14
_cell_angle_alpha   125.72
_cell_angle_beta   125.72
_cell_angle_gamma   80.36
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CsPb3
_chemical_formula_sum   'Cs1 Pb3'
_cell_volume   147.05
_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
  Cs  Cs0  1  0.0  0.0  0.0  1.0
  Pb  Pb1  1  0.0  0.0  0.69  1.0
  Pb  Pb2  1  0.0  0.8  0.34  1.0
  Pb  Pb3  1  0.8  0.0  0.34  1.0

data_CsPb3
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.92
_cell_length_b   7.92
_cell_length_c   6.14
_cell_angle_alpha   90.0
_cell_angle_beta   130.18
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   CsPb3
_chemical_formula_sum   'Cs2 Pb6'
_cell_volume   294.09
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Cs  Cs0  2  0.0  0.0  0.0  1.0
  Pb  Pb1  4  0.06  0.4  0.46  1.0
  Pb  Pb2  2  0.31  0.0  0.31  1.0

Cs Pb Pb Pb
Cs Pb Pb Pb 0 1 o o - 1 3 - o o 1 2 o - o 2 3 - + o 
CsPb3 crystallizes in the monoclinic Cm space group. Cs(1) is bonded in a distorted single-bond geometry to one Pb(1) and four equivalent Pb(2) atoms. The Cs(1)-Pb(1) bond length is 1.91 Å. There are two shorter (3.00 Å) and two longer (4.06 Å) Cs(1)-Pb(2) bond lengths. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a single-bond geometry to one Cs(1) and two equivalent Pb(2) atoms. Both Pb(1)-Pb(2) bond lengths are 1.72 Å. In the second Pb site, Pb(2) is bonded in a 4-coordinate geometry to two equivalent Cs(1), one Pb(1), and one Pb(2) atom. The Pb(2)-Pb(2) bond length is 1.58 Å.