The material described by Bi3NbO7 crystallizes in the monoclinic Cm space group. Nb(1) is bonded in a 5-coordinate geometry to one O(1), one O(6), two equivalent O(4), and three equivalent O(2) atoms. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(3), one O(5), and three equivalent O(7) atoms to form corner-sharing BiO5 trigonal bipyramids. In the second Bi site, Bi(2) is bonded in a 7-coordinate geometry to one O(4), three equivalent O(1), and three equivalent O(3) atoms. In the third Bi site, Bi(3) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(5), and three equivalent O(6) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Nb(1) and three equivalent Bi(2) atoms to form distorted ONbBi3 tetrahedra that share  a cornercorner with one O(6)NbBi3 tetrahedra, corners with three equivalent O(3)Bi4 tetrahedra, corners with three equivalent O(2)Nb3Bi tetrahedra, corners with six equivalent O(1)NbBi3 tetrahedra, and edges with three equivalent O(3)Bi4 tetrahedra. In the second O site, O(2) is bonded to three equivalent Nb(1) and one Bi(3) atom to form distorted ONb3Bi tetrahedra that share corners with three equivalent O(5)Bi4 tetrahedra, corners with three equivalent O(1)NbBi3 tetrahedra, corners with six equivalent O(2)Nb3Bi tetrahedra, and edges with three equivalent O(6)NbBi3 tetrahedra. In the third O site, O(3) is bonded to one Bi(1) and three equivalent Bi(2) atoms to form OBi4 tetrahedra that share  a cornercorner with one O(5)Bi4 tetrahedra, corners with three equivalent O(1)NbBi3 tetrahedra, corners with six equivalent O(3)Bi4 tetrahedra, and edges with three equivalent O(1)NbBi3 tetrahedra. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(1) and one Bi(2) atom. In the fifth O site, O(5) is bonded to one Bi(1) and three equivalent Bi(3) atoms to form OBi4 tetrahedra that share  a cornercorner with one O(3)Bi4 tetrahedra, corners with three equivalent O(2)Nb3Bi tetrahedra, corners with three equivalent O(6)NbBi3 tetrahedra, corners with six equivalent O(5)Bi4 tetrahedra, and edges with three equivalent O(6)NbBi3 tetrahedra. In the sixth O site, O(6) is bonded to one Nb(1) and three equivalent Bi(3) atoms to form distorted ONbBi3 tetrahedra that share  a cornercorner with one O(1)NbBi3 tetrahedra, corners with three equivalent O(5)Bi4 tetrahedra, corners with six equivalent O(6)NbBi3 tetrahedra, edges with three equivalent O(5)Bi4 tetrahedra, and edges with three equivalent O(2)Nb3Bi tetrahedra. In the seventh O site, O(7) is bonded in a trigonal planar geometry to three equivalent Bi(1) atoms. is represented by the CIF file [CIF]
data_NbBi3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.939
_cell_length_b   3.939
_cell_length_c   12.869
_cell_angle_alpha   80.845
_cell_angle_beta   80.845
_cell_angle_gamma   57.497
_symmetry_Int_Tables_number   1
_cell_volume   165.595
_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
  Nb  Nb0  1  0.511  0.511  0.494  1.0
  Bi  Bi1  1  0.965  0.965  0.986  1.0
  Bi  Bi2  1  0.211  0.211  0.262  1.0
  Bi  Bi3  1  0.717  0.717  0.726  1.0
  O  O4  1  0.497  0.497  0.339  1.0
  O  O5  1  0.779  0.779  0.532  1.0
  O  O6  1  0.886  0.886  0.176  1.0
  O  O7  1  0.127  0.127  0.453  1.0
  O  O8  1  0.023  0.023  0.802  1.0
  O  O9  1  0.415  0.415  0.648  1.0
  O  O10  1  0.643  0.643  0.972  1.0
[/CIF]
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The material described by Bi3NbO7 crystallizes in the monoclinic Cm space group. Nb(1) is bonded in a 5-coordinate geometry to one O(1), one O(6), two equivalent O(4), and three equivalent O(2) atoms. There are three inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one O(3), one O(5), and three equivalent O(7) atoms to form corner-sharing BiO5 trigonal bipyramids. In the second Bi site, Bi(2) is bonded in a 7-coordinate geometry to one O(4), three equivalent O(1), and three equivalent O(3) atoms. In the third Bi site, Bi(3) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(5), and three equivalent O(6) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Nb(1) and three equivalent Bi(2) atoms to form distorted ONbBi3 tetrahedra that share  a cornercorner with one O(6)NbBi3 tetrahedra, corners with three equivalent O(3)Bi4 tetrahedra, corners with three equivalent O(2)Nb3Bi tetrahedra, corners with six equivalent O(1)NbBi3 tetrahedra, and edges with three equivalent O(3)Bi4 tetrahedra. In the second O site, O(2) is bonded to three equivalent Nb(1) and one Bi(3) atom to form distorted ONb3Bi tetrahedra that share corners with three equivalent O(5)Bi4 tetrahedra, corners with three equivalent O(1)NbBi3 tetrahedra, corners with six equivalent O(2)Nb3Bi tetrahedra, and edges with three equivalent O(6)NbBi3 tetrahedra. In the third O site, O(3) is bonded to one Bi(1) and three equivalent Bi(2) atoms to form OBi4 tetrahedra that share  a cornercorner with one O(5)Bi4 tetrahedra, corners with three equivalent O(1)NbBi3 tetrahedra, corners with six equivalent O(3)Bi4 tetrahedra, and edges with three equivalent O(1)NbBi3 tetrahedra. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(1) and one Bi(2) atom. In the fifth O site, O(5) is bonded to one Bi(1) and three equivalent Bi(3) atoms to form OBi4 tetrahedra that share  a cornercorner with one O(3)Bi4 tetrahedra, corners with three equivalent O(2)Nb3Bi tetrahedra, corners with three equivalent O(6)NbBi3 tetrahedra, corners with six equivalent O(5)Bi4 tetrahedra, and edges with three equivalent O(6)NbBi3 tetrahedra. In the sixth O site, O(6) is bonded to one Nb(1) and three equivalent Bi(3) atoms to form distorted ONbBi3 tetrahedra that share  a cornercorner with one O(1)NbBi3 tetrahedra, corners with three equivalent O(5)Bi4 tetrahedra, corners with six equivalent O(6)NbBi3 tetrahedra, edges with three equivalent O(5)Bi4 tetrahedra, and edges with three equivalent O(2)Nb3Bi tetrahedra. In the seventh O site, O(7) is bonded in a trigonal planar geometry to three equivalent Bi(1) atoms. is represented by the CIF file [CIF]
data_NbBi3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.939
_cell_length_b   3.939
_cell_length_c   12.869
_cell_angle_alpha   80.845
_cell_angle_beta   80.845
_cell_angle_gamma   57.497
_symmetry_Int_Tables_number   1
_cell_volume   165.595
_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
  Nb  Nb0  1  0.511  0.511  0.494  1.0
  Bi  Bi1  1  0.965  0.965  0.986  1.0
  Bi  Bi2  1  0.211  0.211  0.262  1.0
  Bi  Bi3  1  0.717  0.717  0.726  1.0
  O  O4  1  0.497  0.497  0.339  1.0
  O  O5  1  0.779  0.779  0.532  1.0
  O  O6  1  0.886  0.886  0.176  1.0
  O  O7  1  0.127  0.127  0.453  1.0
  O  O8  1  0.023  0.023  0.802  1.0
  O  O9  1  0.415  0.415  0.648  1.0
  O  O10  1  0.643  0.643  0.972  1.0
[/CIF]
.