The compound described by Zn3Nb2O8 crystallizes in the monoclinic C2/c space group. Nb(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with four equivalent Zn(1)O6 octahedra and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form ZnO6 octahedra that share corners with eight equivalent Nb(1)O6 octahedra and edges with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. In the second Zn site, Zn(2) is bonded in a 4-coordinate geometry to one O(4) and three equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1) and two equivalent Zn(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Nb(1) and one Zn(1) atom. In the third O site, O(3) is bonded to one Nb(1) and three equivalent Zn(2) atoms to form a mixture of edge and corner-sharing ONbZn3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(1) and one Zn(2) atom. is represented by the CIF file [CIF]
data_Nb2Zn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.138
_cell_length_b   10.138
_cell_length_c   5.271
_cell_angle_alpha   89.865
_cell_angle_beta   89.865
_cell_angle_gamma   34.309
_symmetry_Int_Tables_number   1
_cell_volume   305.358
_cell_formula_units_Z   2
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  0.722  0.049  0.263  1.0
  Nb  Nb1  1  0.951  0.278  0.237  1.0
  Nb  Nb2  1  0.278  0.951  0.737  1.0
  Nb  Nb3  1  0.049  0.722  0.763  1.0
  Zn  Zn4  1  0.347  0.653  0.250  1.0
  Zn  Zn5  1  0.653  0.347  0.750  1.0
  Zn  Zn6  1  0.566  0.875  0.238  1.0
  Zn  Zn7  1  0.125  0.434  0.262  1.0
  Zn  Zn8  1  0.875  0.566  0.738  1.0
  Zn  Zn9  1  0.434  0.125  0.762  1.0
  O  O10  1  0.317  0.567  0.914  1.0
  O  O11  1  0.433  0.683  0.586  1.0
  O  O12  1  0.683  0.433  0.086  1.0
  O  O13  1  0.567  0.317  0.414  1.0
  O  O14  1  0.955  0.185  0.575  1.0
  O  O15  1  0.815  0.045  0.925  1.0
  O  O16  1  0.045  0.815  0.425  1.0
  O  O17  1  0.185  0.955  0.075  1.0
  O  O18  1  0.162  0.452  0.632  1.0
  O  O19  1  0.548  0.838  0.868  1.0
  O  O20  1  0.283  0.077  0.443  1.0
  O  O21  1  0.923  0.717  0.057  1.0
  O  O22  1  0.717  0.923  0.557  1.0
  O  O23  1  0.077  0.283  0.943  1.0
  O  O24  1  0.452  0.162  0.132  1.0
  O  O25  1  0.838  0.548  0.368  1.0
[/CIF]
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The compound described by Zn3Nb2O8 crystallizes in the monoclinic C2/c space group. Nb(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form distorted NbO6 octahedra that share corners with four equivalent Zn(1)O6 octahedra and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form ZnO6 octahedra that share corners with eight equivalent Nb(1)O6 octahedra and edges with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. In the second Zn site, Zn(2) is bonded in a 4-coordinate geometry to one O(4) and three equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1) and two equivalent Zn(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to two equivalent Nb(1) and one Zn(1) atom. In the third O site, O(3) is bonded to one Nb(1) and three equivalent Zn(2) atoms to form a mixture of edge and corner-sharing ONbZn3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Nb(1) and one Zn(2) atom. is represented by the CIF file [CIF]
data_Nb2Zn3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.138
_cell_length_b   10.138
_cell_length_c   5.271
_cell_angle_alpha   89.865
_cell_angle_beta   89.865
_cell_angle_gamma   34.309
_symmetry_Int_Tables_number   1
_cell_volume   305.358
_cell_formula_units_Z   2
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  0.722  0.049  0.263  1.0
  Nb  Nb1  1  0.951  0.278  0.237  1.0
  Nb  Nb2  1  0.278  0.951  0.737  1.0
  Nb  Nb3  1  0.049  0.722  0.763  1.0
  Zn  Zn4  1  0.347  0.653  0.250  1.0
  Zn  Zn5  1  0.653  0.347  0.750  1.0
  Zn  Zn6  1  0.566  0.875  0.238  1.0
  Zn  Zn7  1  0.125  0.434  0.262  1.0
  Zn  Zn8  1  0.875  0.566  0.738  1.0
  Zn  Zn9  1  0.434  0.125  0.762  1.0
  O  O10  1  0.317  0.567  0.914  1.0
  O  O11  1  0.433  0.683  0.586  1.0
  O  O12  1  0.683  0.433  0.086  1.0
  O  O13  1  0.567  0.317  0.414  1.0
  O  O14  1  0.955  0.185  0.575  1.0
  O  O15  1  0.815  0.045  0.925  1.0
  O  O16  1  0.045  0.815  0.425  1.0
  O  O17  1  0.185  0.955  0.075  1.0
  O  O18  1  0.162  0.452  0.632  1.0
  O  O19  1  0.548  0.838  0.868  1.0
  O  O20  1  0.283  0.077  0.443  1.0
  O  O21  1  0.923  0.717  0.057  1.0
  O  O22  1  0.717  0.923  0.557  1.0
  O  O23  1  0.077  0.283  0.943  1.0
  O  O24  1  0.452  0.162  0.132  1.0
  O  O25  1  0.838  0.548  0.368  1.0
[/CIF]
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