data_KMgPb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.04
_cell_length_b   5.04
_cell_length_c   4.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KMgPb2
_chemical_formula_sum   'K1 Mg1 Pb2'
_cell_volume   123.31
_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
  K  K0  1  0.52  0.52  0.0  1.0
  Mg  Mg1  1  0.0  0.0  0.0  1.0
  Pb  Pb2  1  0.0  0.52  0.43  1.0
  Pb  Pb3  1  0.52  0.0  0.43  1.0

data_KMgPb2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.13
_cell_length_b   7.13
_cell_length_c   4.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   KMgPb2
_chemical_formula_sum   'K2 Mg2 Pb4'
_cell_volume   246.62
_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
  K  K0  2  0.02  0.5  0.0  1.0
  Mg  Mg1  2  0.0  0.0  0.0  1.0
  Pb  Pb2  4  0.26  0.26  0.43  1.0

K Mg Pb Pb
KMgPb2 crystallizes in the monoclinic Cm space group. K(1) is bonded to four equivalent Mg(1) and eight equivalent Pb(1) atoms to form a mixture of distorted corner and face-sharing KMg4Pb8 cuboctahedra. There are a spread of K(1)-Mg(1) bond distances ranging from 3.42-3.71 Å. There are a spread of K(1)-Pb(1) bond distances ranging from 3.18-3.83 Å. Mg(1) is bonded in a 8-coordinate geometry to four equivalent K(1) and four equivalent Pb(1) atoms. There are two shorter (3.18 Å) and two longer (3.34 Å) Mg(1)-Pb(1) bond lengths. Pb(1) is bonded in a 6-coordinate geometry to four equivalent K(1) and two equivalent Mg(1) atoms.