The material described by Cr6PbO18 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra, and  a faceface with one Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the second Cr site, Cr(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra, and faces with two equivalent Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-5°. Pb(1) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(2), and four equivalent O(4) atoms to form PbO12 cuboctahedra that share faces with four equivalent Cr(1)O6 octahedra and faces with four equivalent Cr(2)O6 octahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Cr(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Cr(1), one Cr(2), and one Pb(1) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Cr(1), one Cr(2), and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Cr(1) and one Pb(1) atom. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Cr(2) and one Pb(1) atom. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Cr(1) atoms. is represented by the CIF file [CIF]
data_Cr6PbO18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.428
_cell_length_b   6.428
_cell_length_c   8.279
_cell_angle_alpha   74.903
_cell_angle_beta   74.903
_cell_angle_gamma   70.310
_symmetry_Int_Tables_number   1
_cell_volume   305.261
_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
  Cr  Cr0  1  0.830  0.342  0.156  1.0
  Cr  Cr1  1  0.500  0.000  0.500  1.0
  Cr  Cr2  1  0.170  0.658  0.844  1.0
  Cr  Cr3  1  0.342  0.830  0.156  1.0
  Cr  Cr4  1  0.000  0.500  0.500  1.0
  Cr  Cr5  1  0.658  0.170  0.844  1.0
  Pb  Pb6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.749  0.251  0.000  1.0
  O  O8  1  0.409  0.919  0.337  1.0
  O  O9  1  0.081  0.591  0.663  1.0
  O  O10  1  0.500  0.000  0.000  1.0
  O  O11  1  0.163  0.671  0.337  1.0
  O  O12  1  0.837  0.329  0.663  1.0
  O  O13  1  0.082  0.082  0.172  1.0
  O  O14  1  0.754  0.754  0.500  1.0
  O  O15  1  0.417  0.417  0.833  1.0
  O  O16  1  0.251  0.749  0.000  1.0
  O  O17  1  0.919  0.409  0.337  1.0
  O  O18  1  0.000  0.500  0.000  1.0
  O  O19  1  0.671  0.163  0.337  1.0
  O  O20  1  0.591  0.081  0.663  1.0
  O  O21  1  0.329  0.837  0.663  1.0
  O  O22  1  0.583  0.583  0.167  1.0
  O  O23  1  0.246  0.246  0.500  1.0
  O  O24  1  0.918  0.918  0.828  1.0
[/CIF]
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The material described by Cr6PbO18 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra, and  a faceface with one Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the second Cr site, Cr(2) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(6) atoms to form CrO6 octahedra that share corners with two equivalent Cr(2)O6 octahedra, corners with four equivalent Cr(1)O6 octahedra, and faces with two equivalent Pb(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 3-5°. Pb(1) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(2), and four equivalent O(4) atoms to form PbO12 cuboctahedra that share faces with four equivalent Cr(1)O6 octahedra and faces with four equivalent Cr(2)O6 octahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Cr(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Cr(1), one Cr(2), and one Pb(1) atom. In the third O site, O(3) is bonded in a linear geometry to two equivalent Cr(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Cr(1), one Cr(2), and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Cr(1) and one Pb(1) atom. In the sixth O site, O(6) is bonded in a linear geometry to two equivalent Cr(2) and one Pb(1) atom. In the seventh O site, O(7) is bonded in a linear geometry to two equivalent Cr(1) atoms. is represented by the CIF file [CIF]
data_Cr6PbO18
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.428
_cell_length_b   6.428
_cell_length_c   8.279
_cell_angle_alpha   74.903
_cell_angle_beta   74.903
_cell_angle_gamma   70.310
_symmetry_Int_Tables_number   1
_cell_volume   305.261
_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
  Cr  Cr0  1  0.830  0.342  0.156  1.0
  Cr  Cr1  1  0.500  0.000  0.500  1.0
  Cr  Cr2  1  0.170  0.658  0.844  1.0
  Cr  Cr3  1  0.342  0.830  0.156  1.0
  Cr  Cr4  1  0.000  0.500  0.500  1.0
  Cr  Cr5  1  0.658  0.170  0.844  1.0
  Pb  Pb6  1  0.000  0.000  0.500  1.0
  O  O7  1  0.749  0.251  0.000  1.0
  O  O8  1  0.409  0.919  0.337  1.0
  O  O9  1  0.081  0.591  0.663  1.0
  O  O10  1  0.500  0.000  0.000  1.0
  O  O11  1  0.163  0.671  0.337  1.0
  O  O12  1  0.837  0.329  0.663  1.0
  O  O13  1  0.082  0.082  0.172  1.0
  O  O14  1  0.754  0.754  0.500  1.0
  O  O15  1  0.417  0.417  0.833  1.0
  O  O16  1  0.251  0.749  0.000  1.0
  O  O17  1  0.919  0.409  0.337  1.0
  O  O18  1  0.000  0.500  0.000  1.0
  O  O19  1  0.671  0.163  0.337  1.0
  O  O20  1  0.591  0.081  0.663  1.0
  O  O21  1  0.329  0.837  0.663  1.0
  O  O22  1  0.583  0.583  0.167  1.0
  O  O23  1  0.246  0.246  0.500  1.0
  O  O24  1  0.918  0.918  0.828  1.0
[/CIF]
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