The material described by PbNb2O6 crystallizes in the monoclinic Pm space group. There are ten inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(15), one O(19), one O(21), one O(24), and two equivalent O(26) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 14-20°. In the second Nb site, Nb(2) is bonded to one O(16), one O(20), one O(22), one O(25), and two equivalent O(27) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 16-39°. In the third Nb site, Nb(3) is bonded to one O(17), one O(21), one O(23), one O(8), and two equivalent O(12) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 15-28°. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one O(18), one O(22), one O(23), one O(9), and two equivalent O(13) atoms. In the fifth Nb site, Nb(5) is bonded to one O(25), one O(28), one O(6), one O(8), and two equivalent O(1) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 1-46°. In the sixth Nb site, Nb(6) is bonded in a 6-coordinate geometry to one O(24), one O(29), one O(7), one O(9), and two equivalent O(2) atoms. In the seventh Nb site, Nb(7) is bonded to one O(10), one O(11), one O(17), one O(18), and two equivalent O(14) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 9-38°. In the eighth Nb site, Nb(8) is bonded to one O(10), one O(19), one O(3), one O(6), and two equivalent O(4) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 1-38°. In the ninth Nb site, Nb(9) is bonded to one O(11), one O(20), one O(3), one O(7), and two equivalent O(5) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 16-38°. In the tenth Nb site, Nb(10) is bonded to one O(15), one O(16), one O(28), one O(29), and two equivalent O(30) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 14-46°. There are five inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 6-coordinate geometry to one O(26), one O(4), two equivalent O(10), and two equivalent O(19) atoms. In the second Pb site, Pb(2) is bonded in a 8-coordinate geometry to one O(27), one O(5), two equivalent O(11), two equivalent O(20), and two equivalent O(25) atoms. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to one O(30) and two equivalent O(28) atoms. In the fourth Pb site, Pb(4) is bonded in a 4-coordinate geometry to one O(12), one O(13), and two equivalent O(23) atoms. In the fifth Pb site, Pb(5) is bonded in a 6-coordinate geometry to one O(13), one O(2), two equivalent O(7), and two equivalent O(9) atoms. There are thirty inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Nb(5) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Nb(6) and one Pb(5) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Nb(8) and one Nb(9) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(8) and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Nb(9) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(5) and one Nb(8) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Nb(6), one Nb(9), and two equivalent Pb(5) atoms. In the eighth O site, O(8) is bonded in a linear geometry to one Nb(3) and one Nb(5) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Nb(4), one Nb(6), and two equivalent Pb(5) atoms. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Nb(7), one Nb(8), and two equivalent Pb(1) atoms. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Nb(7), one Nb(9), and two equivalent Pb(2) atoms. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to two equivalent Nb(3) and one Pb(4) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to two equivalent Nb(4), one Pb(4), and one Pb(5) atom. In the fourteenth O site, O(14) is bonded in a linear geometry to two equivalent Nb(7) atoms. In the fifteenth O site, O(15) is bonded in a linear geometry to one Nb(1) and one Nb(10) atom. In the sixteenth O site, O(16) is bonded in a linear geometry to one Nb(10) and one Nb(2) atom. In the seventeenth O site, O(17) is bonded in a bent 150 degrees geometry to one Nb(3) and one Nb(7) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Nb(4) and one Nb(7) atom. In the nineteenth O site, O(19) is bonded in a distorted bent 150 degrees geometry to one Nb(1), one Nb(8), and two equivalent Pb(1) atoms. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Nb(2), one Nb(9), and two equivalent Pb(2) atoms. In the twenty-first O site, O(21) is bonded in a distorted linear geometry to one Nb(1) and one Nb(3) atom. In the twenty-second O site, O(22) is bonded in a distorted linear geometry to one Nb(2) and one Nb(4) atom. In the twenty-third O site, O(23) is bonded to one Nb(3), one Nb(4), and two equivalent Pb(4) atoms to form distorted corner-sharing ONb2Pb2 tetrahedra. In the twenty-fourth O site, O(24) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(6) atom. In the twenty-fifth O site, O(25) is bonded in a 2-coordinate geometry to one Nb(2), one Nb(5), and two equivalent Pb(2) atoms. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to two equivalent Nb(1) and one Pb(1) atom. In the twenty-seventh O site, O(27) is bonded in a 3-coordinate geometry to two equivalent Nb(2) and one Pb(2) atom. In the twenty-eighth O site, O(28) is bonded to one Nb(10), one Nb(5), and two equivalent Pb(3) atoms to form distorted corner-sharing ONb2Pb2 tetrahedra. In the twenty-ninth O site, O(29) is bonded in a 2-coordinate geometry to one Nb(10) and one Nb(6) atom. In the thirtieth O site, O(30) is bonded in a distorted T-shaped geometry to two equivalent Nb(10) and one Pb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2PbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.947
_cell_length_b   12.991
_cell_length_c   13.074
_cell_angle_alpha   87.780
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   669.890
_cell_formula_units_Z   5
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  0.000  0.938  0.297  1.0
  Nb  Nb1  1  0.000  0.292  0.932  1.0
  Nb  Nb2  1  0.000  0.211  0.440  1.0
  Nb  Nb3  1  0.000  0.431  0.220  1.0
  Nb  Nb4  1  0.000  0.085  0.712  1.0
  Nb  Nb5  1  0.000  0.719  0.085  1.0
  Nb  Nb6  1  0.000  0.503  0.505  1.0
  Nb  Nb7  1  0.000  0.804  0.576  1.0
  Nb  Nb8  1  0.000  0.586  0.785  1.0
  Nb  Nb9  1  0.000  0.001  0.003  1.0
  Pb  Pb10  1  0.500  0.718  0.380  1.0
  Pb  Pb11  1  0.500  0.370  0.723  1.0
  Pb  Pb12  1  0.500  0.874  0.837  1.0
  Pb  Pb13  1  0.500  0.197  0.220  1.0
  Pb  Pb14  1  0.500  0.513  0.008  1.0
  O  O15  1  0.500  0.066  0.712  1.0
  O  O16  1  0.500  0.689  0.070  1.0
  O  O17  1  0.000  0.715  0.709  1.0
  O  O18  1  0.500  0.782  0.557  1.0
  O  O19  1  0.500  0.558  0.783  1.0
  O  O20  1  0.000  0.926  0.637  1.0
  O  O21  1  0.000  0.626  0.922  1.0
  O  O22  1  0.000  0.133  0.563  1.0
  O  O23  1  0.000  0.554  0.126  1.0
  O  O24  1  0.000  0.650  0.485  1.0
  O  O25  1  0.000  0.493  0.652  1.0
  O  O26  1  0.500  0.204  0.403  1.0
  O  O27  1  0.500  0.408  0.197  1.0
  O  O28  1  0.500  0.495  0.498  1.0
  O  O29  1  0.000  0.988  0.147  1.0
  O  O30  1  0.000  0.146  0.989  1.0
  O  O31  1  0.000  0.339  0.494  1.0
  O  O32  1  0.000  0.496  0.340  1.0
  O  O33  1  0.000  0.848  0.424  1.0
  O  O34  1  0.000  0.420  0.842  1.0
  O  O35  1  0.000  0.071  0.341  1.0
  O  O36  1  0.000  0.351  0.058  1.0
  O  O37  1  0.000  0.281  0.277  1.0
  O  O38  1  0.000  0.775  0.212  1.0
  O  O39  1  0.000  0.214  0.769  1.0
  O  O40  1  0.500  0.912  0.291  1.0
  O  O41  1  0.500  0.288  0.907  1.0
  O  O42  1  0.000  0.984  0.837  1.0
  O  O43  1  0.000  0.834  0.991  1.0
  O  O44  1  0.500  0.981  0.982  1.0
[/CIF]
.
The material described by PbNb2O6 crystallizes in the monoclinic Pm space group. There are ten inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(15), one O(19), one O(21), one O(24), and two equivalent O(26) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 14-20°. In the second Nb site, Nb(2) is bonded to one O(16), one O(20), one O(22), one O(25), and two equivalent O(27) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 16-39°. In the third Nb site, Nb(3) is bonded to one O(17), one O(21), one O(23), one O(8), and two equivalent O(12) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 15-28°. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one O(18), one O(22), one O(23), one O(9), and two equivalent O(13) atoms. In the fifth Nb site, Nb(5) is bonded to one O(25), one O(28), one O(6), one O(8), and two equivalent O(1) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 1-46°. In the sixth Nb site, Nb(6) is bonded in a 6-coordinate geometry to one O(24), one O(29), one O(7), one O(9), and two equivalent O(2) atoms. In the seventh Nb site, Nb(7) is bonded to one O(10), one O(11), one O(17), one O(18), and two equivalent O(14) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 9-38°. In the eighth Nb site, Nb(8) is bonded to one O(10), one O(19), one O(3), one O(6), and two equivalent O(4) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 1-38°. In the ninth Nb site, Nb(9) is bonded to one O(11), one O(20), one O(3), one O(7), and two equivalent O(5) atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 16-38°. In the tenth Nb site, Nb(10) is bonded to one O(15), one O(16), one O(28), one O(29), and two equivalent O(30) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 14-46°. There are five inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a 6-coordinate geometry to one O(26), one O(4), two equivalent O(10), and two equivalent O(19) atoms. In the second Pb site, Pb(2) is bonded in a 8-coordinate geometry to one O(27), one O(5), two equivalent O(11), two equivalent O(20), and two equivalent O(25) atoms. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to one O(30) and two equivalent O(28) atoms. In the fourth Pb site, Pb(4) is bonded in a 4-coordinate geometry to one O(12), one O(13), and two equivalent O(23) atoms. In the fifth Pb site, Pb(5) is bonded in a 6-coordinate geometry to one O(13), one O(2), two equivalent O(7), and two equivalent O(9) atoms. There are thirty inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Nb(5) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Nb(6) and one Pb(5) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Nb(8) and one Nb(9) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(8) and one Pb(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Nb(9) and one Pb(2) atom. In the sixth O site, O(6) is bonded in a linear geometry to one Nb(5) and one Nb(8) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to one Nb(6), one Nb(9), and two equivalent Pb(5) atoms. In the eighth O site, O(8) is bonded in a linear geometry to one Nb(3) and one Nb(5) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Nb(4), one Nb(6), and two equivalent Pb(5) atoms. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Nb(7), one Nb(8), and two equivalent Pb(1) atoms. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Nb(7), one Nb(9), and two equivalent Pb(2) atoms. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to two equivalent Nb(3) and one Pb(4) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to two equivalent Nb(4), one Pb(4), and one Pb(5) atom. In the fourteenth O site, O(14) is bonded in a linear geometry to two equivalent Nb(7) atoms. In the fifteenth O site, O(15) is bonded in a linear geometry to one Nb(1) and one Nb(10) atom. In the sixteenth O site, O(16) is bonded in a linear geometry to one Nb(10) and one Nb(2) atom. In the seventeenth O site, O(17) is bonded in a bent 150 degrees geometry to one Nb(3) and one Nb(7) atom. In the eighteenth O site, O(18) is bonded in a bent 150 degrees geometry to one Nb(4) and one Nb(7) atom. In the nineteenth O site, O(19) is bonded in a distorted bent 150 degrees geometry to one Nb(1), one Nb(8), and two equivalent Pb(1) atoms. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Nb(2), one Nb(9), and two equivalent Pb(2) atoms. In the twenty-first O site, O(21) is bonded in a distorted linear geometry to one Nb(1) and one Nb(3) atom. In the twenty-second O site, O(22) is bonded in a distorted linear geometry to one Nb(2) and one Nb(4) atom. In the twenty-third O site, O(23) is bonded to one Nb(3), one Nb(4), and two equivalent Pb(4) atoms to form distorted corner-sharing ONb2Pb2 tetrahedra. In the twenty-fourth O site, O(24) is bonded in a distorted bent 150 degrees geometry to one Nb(1) and one Nb(6) atom. In the twenty-fifth O site, O(25) is bonded in a 2-coordinate geometry to one Nb(2), one Nb(5), and two equivalent Pb(2) atoms. In the twenty-sixth O site, O(26) is bonded in a distorted bent 150 degrees geometry to two equivalent Nb(1) and one Pb(1) atom. In the twenty-seventh O site, O(27) is bonded in a 3-coordinate geometry to two equivalent Nb(2) and one Pb(2) atom. In the twenty-eighth O site, O(28) is bonded to one Nb(10), one Nb(5), and two equivalent Pb(3) atoms to form distorted corner-sharing ONb2Pb2 tetrahedra. In the twenty-ninth O site, O(29) is bonded in a 2-coordinate geometry to one Nb(10) and one Nb(6) atom. In the thirtieth O site, O(30) is bonded in a distorted T-shaped geometry to two equivalent Nb(10) and one Pb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2PbO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.947
_cell_length_b   12.991
_cell_length_c   13.074
_cell_angle_alpha   87.780
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   669.890
_cell_formula_units_Z   5
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  0.000  0.938  0.297  1.0
  Nb  Nb1  1  0.000  0.292  0.932  1.0
  Nb  Nb2  1  0.000  0.211  0.440  1.0
  Nb  Nb3  1  0.000  0.431  0.220  1.0
  Nb  Nb4  1  0.000  0.085  0.712  1.0
  Nb  Nb5  1  0.000  0.719  0.085  1.0
  Nb  Nb6  1  0.000  0.503  0.505  1.0
  Nb  Nb7  1  0.000  0.804  0.576  1.0
  Nb  Nb8  1  0.000  0.586  0.785  1.0
  Nb  Nb9  1  0.000  0.001  0.003  1.0
  Pb  Pb10  1  0.500  0.718  0.380  1.0
  Pb  Pb11  1  0.500  0.370  0.723  1.0
  Pb  Pb12  1  0.500  0.874  0.837  1.0
  Pb  Pb13  1  0.500  0.197  0.220  1.0
  Pb  Pb14  1  0.500  0.513  0.008  1.0
  O  O15  1  0.500  0.066  0.712  1.0
  O  O16  1  0.500  0.689  0.070  1.0
  O  O17  1  0.000  0.715  0.709  1.0
  O  O18  1  0.500  0.782  0.557  1.0
  O  O19  1  0.500  0.558  0.783  1.0
  O  O20  1  0.000  0.926  0.637  1.0
  O  O21  1  0.000  0.626  0.922  1.0
  O  O22  1  0.000  0.133  0.563  1.0
  O  O23  1  0.000  0.554  0.126  1.0
  O  O24  1  0.000  0.650  0.485  1.0
  O  O25  1  0.000  0.493  0.652  1.0
  O  O26  1  0.500  0.204  0.403  1.0
  O  O27  1  0.500  0.408  0.197  1.0
  O  O28  1  0.500  0.495  0.498  1.0
  O  O29  1  0.000  0.988  0.147  1.0
  O  O30  1  0.000  0.146  0.989  1.0
  O  O31  1  0.000  0.339  0.494  1.0
  O  O32  1  0.000  0.496  0.340  1.0
  O  O33  1  0.000  0.848  0.424  1.0
  O  O34  1  0.000  0.420  0.842  1.0
  O  O35  1  0.000  0.071  0.341  1.0
  O  O36  1  0.000  0.351  0.058  1.0
  O  O37  1  0.000  0.281  0.277  1.0
  O  O38  1  0.000  0.775  0.212  1.0
  O  O39  1  0.000  0.214  0.769  1.0
  O  O40  1  0.500  0.912  0.291  1.0
  O  O41  1  0.500  0.288  0.907  1.0
  O  O42  1  0.000  0.984  0.837  1.0
  O  O43  1  0.000  0.834  0.991  1.0
  O  O44  1  0.500  0.981  0.982  1.0
[/CIF]
.