The material described by FeTaO4 is Hydrophilite-derived structured and crystallizes in the orthorhombic Cmm2 space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the third Ta site, Ta(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-53°. In the third Fe site, Fe(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Ta(3)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(2), and one Fe(3) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(1), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(3), and one Fe(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(2), and one Fe(3) atom. is represented by the CIF file [CIF]
data_TaFeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.740
_cell_length_b   4.740
_cell_length_c   9.233
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.541
_symmetry_Int_Tables_number   1
_cell_volume   207.431
_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
  Ta  Ta0  1  0.000  0.000  0.337  1.0
  Ta  Ta1  1  0.500  0.500  0.157  1.0
  Ta  Ta2  1  0.000  0.000  0.678  1.0
  Fe  Fe3  1  0.500  0.500  0.504  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Fe  Fe5  1  0.500  0.500  0.827  1.0
  O  O6  1  0.803  0.197  0.830  1.0
  O  O7  1  0.197  0.803  0.830  1.0
  O  O8  1  0.302  0.302  0.329  1.0
  O  O9  1  0.698  0.698  0.329  1.0
  O  O10  1  0.199  0.801  0.171  1.0
  O  O11  1  0.801  0.199  0.171  1.0
  O  O12  1  0.701  0.701  0.665  1.0
  O  O13  1  0.299  0.299  0.665  1.0
  O  O14  1  0.807  0.193  0.497  1.0
  O  O15  1  0.193  0.807  0.497  1.0
  O  O16  1  0.303  0.303  0.005  1.0
  O  O17  1  0.697  0.697  0.005  1.0
[/CIF]
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The material described by FeTaO4 is Hydrophilite-derived structured and crystallizes in the orthorhombic Cmm2 space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the third Ta site, Ta(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-53°. In the third Fe site, Fe(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with four equivalent Ta(3)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(2), and one Fe(3) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(1), and one Fe(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(3), and one Fe(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(2), and one Fe(3) atom. is represented by the CIF file [CIF]
data_TaFeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.740
_cell_length_b   4.740
_cell_length_c   9.233
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.541
_symmetry_Int_Tables_number   1
_cell_volume   207.431
_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
  Ta  Ta0  1  0.000  0.000  0.337  1.0
  Ta  Ta1  1  0.500  0.500  0.157  1.0
  Ta  Ta2  1  0.000  0.000  0.678  1.0
  Fe  Fe3  1  0.500  0.500  0.504  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Fe  Fe5  1  0.500  0.500  0.827  1.0
  O  O6  1  0.803  0.197  0.830  1.0
  O  O7  1  0.197  0.803  0.830  1.0
  O  O8  1  0.302  0.302  0.329  1.0
  O  O9  1  0.698  0.698  0.329  1.0
  O  O10  1  0.199  0.801  0.171  1.0
  O  O11  1  0.801  0.199  0.171  1.0
  O  O12  1  0.701  0.701  0.665  1.0
  O  O13  1  0.299  0.299  0.665  1.0
  O  O14  1  0.807  0.193  0.497  1.0
  O  O15  1  0.193  0.807  0.497  1.0
  O  O16  1  0.303  0.303  0.005  1.0
  O  O17  1  0.697  0.697  0.005  1.0
[/CIF]
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