The crystal structure described by PbNb2O6 crystallizes in the trigonal R3m space group. Nb(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 27-43°. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a distorted T-shaped geometry to three equivalent O(4) atoms. In the second Pb site, Pb(2) is bonded in a 3-coordinate geometry to three equivalent O(3) atoms. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to three equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Nb(1), one Pb(2), and one Pb(3) atom to form distorted edge-sharing ONb2Pb2 tetrahedra. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Nb(1) and one Pb(1) atom. In the third O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2PbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.243
_cell_length_b   7.243
_cell_length_c   7.243
_cell_angle_alpha   94.231
_cell_angle_beta   94.231
_cell_angle_gamma   94.231
_symmetry_Int_Tables_number   1
_cell_volume   376.670
_cell_formula_units_Z   3
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
  Nb  Nb0  1  0.517  0.160  0.818  1.0
  Nb  Nb1  1  0.818  0.517  0.160  1.0
  Nb  Nb2  1  0.160  0.818  0.517  1.0
  Nb  Nb3  1  0.818  0.160  0.517  1.0
  Nb  Nb4  1  0.517  0.818  0.160  1.0
  Nb  Nb5  1  0.160  0.517  0.818  1.0
  Pb  Pb6  1  0.995  0.995  0.995  1.0
  Pb  Pb7  1  0.652  0.652  0.652  1.0
  Pb  Pb8  1  0.348  0.348  0.348  1.0
  O  O9  1  0.062  0.515  0.062  1.0
  O  O10  1  0.062  0.062  0.515  1.0
  O  O11  1  0.515  0.062  0.062  1.0
  O  O12  1  0.400  0.954  0.678  1.0
  O  O13  1  0.678  0.400  0.954  1.0
  O  O14  1  0.954  0.678  0.400  1.0
  O  O15  1  0.678  0.954  0.400  1.0
  O  O16  1  0.400  0.678  0.954  1.0
  O  O17  1  0.954  0.400  0.678  1.0
  O  O18  1  0.298  0.579  0.579  1.0
  O  O19  1  0.579  0.298  0.579  1.0
  O  O20  1  0.579  0.579  0.298  1.0
  O  O21  1  0.774  0.066  0.774  1.0
  O  O22  1  0.774  0.774  0.066  1.0
  O  O23  1  0.066  0.774  0.774  1.0
  O  O24  1  0.298  0.843  0.298  1.0
  O  O25  1  0.298  0.298  0.843  1.0
  O  O26  1  0.843  0.298  0.298  1.0
[/CIF]
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The crystal structure described by PbNb2O6 crystallizes in the trigonal R3m space group. Nb(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 27-43°. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a distorted T-shaped geometry to three equivalent O(4) atoms. In the second Pb site, Pb(2) is bonded in a 3-coordinate geometry to three equivalent O(3) atoms. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to three equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Nb(1), one Pb(2), and one Pb(3) atom to form distorted edge-sharing ONb2Pb2 tetrahedra. In the second O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Nb(1) and one Pb(1) atom. In the third O site, O(5) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. In the fourth O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. In the fifth O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent Nb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2PbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.243
_cell_length_b   7.243
_cell_length_c   7.243
_cell_angle_alpha   94.231
_cell_angle_beta   94.231
_cell_angle_gamma   94.231
_symmetry_Int_Tables_number   1
_cell_volume   376.670
_cell_formula_units_Z   3
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
  Nb  Nb0  1  0.517  0.160  0.818  1.0
  Nb  Nb1  1  0.818  0.517  0.160  1.0
  Nb  Nb2  1  0.160  0.818  0.517  1.0
  Nb  Nb3  1  0.818  0.160  0.517  1.0
  Nb  Nb4  1  0.517  0.818  0.160  1.0
  Nb  Nb5  1  0.160  0.517  0.818  1.0
  Pb  Pb6  1  0.995  0.995  0.995  1.0
  Pb  Pb7  1  0.652  0.652  0.652  1.0
  Pb  Pb8  1  0.348  0.348  0.348  1.0
  O  O9  1  0.062  0.515  0.062  1.0
  O  O10  1  0.062  0.062  0.515  1.0
  O  O11  1  0.515  0.062  0.062  1.0
  O  O12  1  0.400  0.954  0.678  1.0
  O  O13  1  0.678  0.400  0.954  1.0
  O  O14  1  0.954  0.678  0.400  1.0
  O  O15  1  0.678  0.954  0.400  1.0
  O  O16  1  0.400  0.678  0.954  1.0
  O  O17  1  0.954  0.400  0.678  1.0
  O  O18  1  0.298  0.579  0.579  1.0
  O  O19  1  0.579  0.298  0.579  1.0
  O  O20  1  0.579  0.579  0.298  1.0
  O  O21  1  0.774  0.066  0.774  1.0
  O  O22  1  0.774  0.774  0.066  1.0
  O  O23  1  0.066  0.774  0.774  1.0
  O  O24  1  0.298  0.843  0.298  1.0
  O  O25  1  0.298  0.298  0.843  1.0
  O  O26  1  0.843  0.298  0.298  1.0
[/CIF]
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