The material structure described by Zn4Ta2O9 is Ilmenite-like structured and crystallizes in the trigonal P-3c1 space group. Ta(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted TaO6 octahedra that share corners with six equivalent Zn(1)O6 octahedra and  a faceface with one Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to six equivalent O(2) atoms to form ZnO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and edges with three equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. In the second Zn site, Zn(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ta(1) and two equivalent Zn(2) atoms to form distorted OTa2Zn2 trigonal pyramids that share corners with four equivalent O(1)Ta2Zn2 trigonal pyramids, corners with eight equivalent O(2)TaZn3 trigonal pyramids, edges with two equivalent O(1)Ta2Zn2 trigonal pyramids, and edges with two equivalent O(2)TaZn3 trigonal pyramids. In the second O site, O(2) is bonded to one Ta(1), one Zn(2), and two equivalent Zn(1) atoms to form distorted OTaZn3 trigonal pyramids that share corners with four equivalent O(1)Ta2Zn2 trigonal pyramids, corners with eight equivalent O(2)TaZn3 trigonal pyramids,  an edgeedge with one O(1)Ta2Zn2 trigonal pyramid, and edges with three equivalent O(2)TaZn3 trigonal pyramids. is represented by the CIF file [CIF]
data_Ta2Zn4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.244
_cell_length_b   5.244
_cell_length_c   14.347
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   341.647
_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
  Ta  Ta0  1  0.000  0.000  0.141  1.0
  Ta  Ta1  1  0.000  0.000  0.359  1.0
  Ta  Ta2  1  0.000  0.000  0.641  1.0
  Ta  Ta3  1  0.000  0.000  0.859  1.0
  Zn  Zn4  1  0.333  0.667  0.018  1.0
  Zn  Zn5  1  0.333  0.667  0.303  1.0
  Zn  Zn6  1  0.333  0.667  0.518  1.0
  Zn  Zn7  1  0.333  0.667  0.803  1.0
  Zn  Zn8  1  0.667  0.333  0.197  1.0
  Zn  Zn9  1  0.667  0.333  0.482  1.0
  Zn  Zn10  1  0.667  0.333  0.697  1.0
  Zn  Zn11  1  0.667  0.333  0.982  1.0
  O  O12  1  0.000  0.715  0.750  1.0
  O  O13  1  0.024  0.683  0.416  1.0
  O  O14  1  0.317  0.976  0.916  1.0
  O  O15  1  0.024  0.340  0.916  1.0
  O  O16  1  0.000  0.285  0.250  1.0
  O  O17  1  0.285  0.285  0.750  1.0
  O  O18  1  0.317  0.340  0.416  1.0
  O  O19  1  0.660  0.976  0.416  1.0
  O  O20  1  0.340  0.317  0.084  1.0
  O  O21  1  0.285  0.000  0.250  1.0
  O  O22  1  0.660  0.683  0.916  1.0
  O  O23  1  0.340  0.024  0.584  1.0
  O  O24  1  0.683  0.660  0.584  1.0
  O  O25  1  0.715  0.715  0.250  1.0
  O  O26  1  0.976  0.660  0.084  1.0
  O  O27  1  0.683  0.024  0.084  1.0
  O  O28  1  0.715  0.000  0.750  1.0
  O  O29  1  0.976  0.317  0.584  1.0
[/CIF]
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The material structure described by Zn4Ta2O9 is Ilmenite-like structured and crystallizes in the trigonal P-3c1 space group. Ta(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted TaO6 octahedra that share corners with six equivalent Zn(1)O6 octahedra and  a faceface with one Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to six equivalent O(2) atoms to form ZnO6 octahedra that share corners with six equivalent Ta(1)O6 octahedra and edges with three equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-57°. In the second Zn site, Zn(2) is bonded in a 6-coordinate geometry to three equivalent O(1) and three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ta(1) and two equivalent Zn(2) atoms to form distorted OTa2Zn2 trigonal pyramids that share corners with four equivalent O(1)Ta2Zn2 trigonal pyramids, corners with eight equivalent O(2)TaZn3 trigonal pyramids, edges with two equivalent O(1)Ta2Zn2 trigonal pyramids, and edges with two equivalent O(2)TaZn3 trigonal pyramids. In the second O site, O(2) is bonded to one Ta(1), one Zn(2), and two equivalent Zn(1) atoms to form distorted OTaZn3 trigonal pyramids that share corners with four equivalent O(1)Ta2Zn2 trigonal pyramids, corners with eight equivalent O(2)TaZn3 trigonal pyramids,  an edgeedge with one O(1)Ta2Zn2 trigonal pyramid, and edges with three equivalent O(2)TaZn3 trigonal pyramids. is represented by the CIF file [CIF]
data_Ta2Zn4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.244
_cell_length_b   5.244
_cell_length_c   14.347
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   341.647
_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
  Ta  Ta0  1  0.000  0.000  0.141  1.0
  Ta  Ta1  1  0.000  0.000  0.359  1.0
  Ta  Ta2  1  0.000  0.000  0.641  1.0
  Ta  Ta3  1  0.000  0.000  0.859  1.0
  Zn  Zn4  1  0.333  0.667  0.018  1.0
  Zn  Zn5  1  0.333  0.667  0.303  1.0
  Zn  Zn6  1  0.333  0.667  0.518  1.0
  Zn  Zn7  1  0.333  0.667  0.803  1.0
  Zn  Zn8  1  0.667  0.333  0.197  1.0
  Zn  Zn9  1  0.667  0.333  0.482  1.0
  Zn  Zn10  1  0.667  0.333  0.697  1.0
  Zn  Zn11  1  0.667  0.333  0.982  1.0
  O  O12  1  0.000  0.715  0.750  1.0
  O  O13  1  0.024  0.683  0.416  1.0
  O  O14  1  0.317  0.976  0.916  1.0
  O  O15  1  0.024  0.340  0.916  1.0
  O  O16  1  0.000  0.285  0.250  1.0
  O  O17  1  0.285  0.285  0.750  1.0
  O  O18  1  0.317  0.340  0.416  1.0
  O  O19  1  0.660  0.976  0.416  1.0
  O  O20  1  0.340  0.317  0.084  1.0
  O  O21  1  0.285  0.000  0.250  1.0
  O  O22  1  0.660  0.683  0.916  1.0
  O  O23  1  0.340  0.024  0.584  1.0
  O  O24  1  0.683  0.660  0.584  1.0
  O  O25  1  0.715  0.715  0.250  1.0
  O  O26  1  0.976  0.660  0.084  1.0
  O  O27  1  0.683  0.024  0.084  1.0
  O  O28  1  0.715  0.000  0.750  1.0
  O  O29  1  0.976  0.317  0.584  1.0
[/CIF]
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