The compound described by MgTa2(FeO4)2 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-53°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-53°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(2)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-52°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ta(1), one Fe(1), and one Fe(2) 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(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Ta(2), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Ta(1), one Ta(2), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing OMgTa2Fe trigonal pyramids. is represented by the CIF card [CIF]
data_MgTa2(FeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.966
_cell_length_b   5.199
_cell_length_c   5.971
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   91.061
_symmetry_Int_Tables_number   1
_cell_volume   154.115
_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
  Mg  Mg0  1  0.000  0.750  0.380  1.0
  Ta  Ta1  1  0.000  0.750  0.845  1.0
  Ta  Ta2  1  0.000  0.250  0.149  1.0
  Fe  Fe3  1  0.500  0.750  0.345  1.0
  Fe  Fe4  1  0.500  0.250  0.658  1.0
  O  O5  1  0.246  0.890  0.626  1.0
  O  O6  1  0.208  0.428  0.888  1.0
  O  O7  1  0.242  0.420  0.364  1.0
  O  O8  1  0.210  0.924  0.124  1.0
  O  O9  1  0.792  0.072  0.888  1.0
  O  O10  1  0.754  0.610  0.626  1.0
  O  O11  1  0.790  0.576  0.124  1.0
  O  O12  1  0.758  0.080  0.364  1.0
[/CIF]
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The compound described by MgTa2(FeO4)2 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Ta(1)O6 octahedra, edges with two equivalent Ta(2)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-53°. In the second Ta site, Ta(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-53°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(2)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-52°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Ta(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Ta(1), one Fe(1), and one Fe(2) 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(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Ta(2), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Ta(1), one Ta(2), and one Fe(1) atom to form a mixture of distorted corner and edge-sharing OMgTa2Fe trigonal pyramids. is represented by the CIF card [CIF]
data_MgTa2(FeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.966
_cell_length_b   5.199
_cell_length_c   5.971
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   91.061
_symmetry_Int_Tables_number   1
_cell_volume   154.115
_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
  Mg  Mg0  1  0.000  0.750  0.380  1.0
  Ta  Ta1  1  0.000  0.750  0.845  1.0
  Ta  Ta2  1  0.000  0.250  0.149  1.0
  Fe  Fe3  1  0.500  0.750  0.345  1.0
  Fe  Fe4  1  0.500  0.250  0.658  1.0
  O  O5  1  0.246  0.890  0.626  1.0
  O  O6  1  0.208  0.428  0.888  1.0
  O  O7  1  0.242  0.420  0.364  1.0
  O  O8  1  0.210  0.924  0.124  1.0
  O  O9  1  0.792  0.072  0.888  1.0
  O  O10  1  0.754  0.610  0.626  1.0
  O  O11  1  0.790  0.576  0.124  1.0
  O  O12  1  0.758  0.080  0.364  1.0
[/CIF]
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