The material structure described by MgTa2(FeO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(3) and four equivalent O(2) atoms. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 12°. Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), and three equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ta(1) and one Fe(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Ta(1), and one Fe(1) atom to form distorted OMg2TaFe tetrahedra that share corners with four equivalent O(2)Mg2TaFe tetrahedra, corners with four equivalent O(4)TaFe3 trigonal pyramids, and  an edgeedge with one O(2)Mg2TaFe tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Ta(1), and one Fe(1) atom. In the fourth O site, O(4) is bonded to one Ta(1) and three equivalent Fe(1) atoms to form distorted OTaFe3 trigonal pyramids that share corners with four equivalent O(2)Mg2TaFe tetrahedra, corners with two equivalent O(4)TaFe3 trigonal pyramids, and edges with two equivalent O(4)TaFe3 trigonal pyramids. is represented by the CIF card [CIF]
data_MgTa2(FeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.793
_cell_length_b   6.793
_cell_length_c   6.808
_cell_angle_alpha   75.674
_cell_angle_beta   104.326
_cell_angle_gamma   146.710
_symmetry_Int_Tables_number   1
_cell_volume   166.562
_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  0.500  0.500  0.500  1.0
  Ta  Ta1  1  0.097  0.903  0.210  1.0
  Ta  Ta2  1  0.903  0.097  0.790  1.0
  Fe  Fe3  1  0.200  0.800  0.798  1.0
  Fe  Fe4  1  0.800  0.200  0.202  1.0
  O  O5  1  0.061  0.939  0.889  1.0
  O  O6  1  0.100  0.900  0.499  1.0
  O  O7  1  0.399  0.601  0.760  1.0
  O  O8  1  0.246  0.754  0.177  1.0
  O  O9  1  0.754  0.246  0.823  1.0
  O  O10  1  0.601  0.399  0.240  1.0
  O  O11  1  0.900  0.100  0.501  1.0
  O  O12  1  0.939  0.061  0.111  1.0
[/CIF]
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The material structure described by MgTa2(FeO4)2 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded in a distorted hexagonal planar geometry to two equivalent O(3) and four equivalent O(2) atoms. Ta(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 12°. Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), and three equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ta(1) and one Fe(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Ta(1), and one Fe(1) atom to form distorted OMg2TaFe tetrahedra that share corners with four equivalent O(2)Mg2TaFe tetrahedra, corners with four equivalent O(4)TaFe3 trigonal pyramids, and  an edgeedge with one O(2)Mg2TaFe tetrahedra. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Ta(1), and one Fe(1) atom. In the fourth O site, O(4) is bonded to one Ta(1) and three equivalent Fe(1) atoms to form distorted OTaFe3 trigonal pyramids that share corners with four equivalent O(2)Mg2TaFe tetrahedra, corners with two equivalent O(4)TaFe3 trigonal pyramids, and edges with two equivalent O(4)TaFe3 trigonal pyramids. is represented by the CIF card [CIF]
data_MgTa2(FeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.793
_cell_length_b   6.793
_cell_length_c   6.808
_cell_angle_alpha   75.674
_cell_angle_beta   104.326
_cell_angle_gamma   146.710
_symmetry_Int_Tables_number   1
_cell_volume   166.562
_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  0.500  0.500  0.500  1.0
  Ta  Ta1  1  0.097  0.903  0.210  1.0
  Ta  Ta2  1  0.903  0.097  0.790  1.0
  Fe  Fe3  1  0.200  0.800  0.798  1.0
  Fe  Fe4  1  0.800  0.200  0.202  1.0
  O  O5  1  0.061  0.939  0.889  1.0
  O  O6  1  0.100  0.900  0.499  1.0
  O  O7  1  0.399  0.601  0.760  1.0
  O  O8  1  0.246  0.754  0.177  1.0
  O  O9  1  0.754  0.246  0.823  1.0
  O  O10  1  0.601  0.399  0.240  1.0
  O  O11  1  0.900  0.100  0.501  1.0
  O  O12  1  0.939  0.061  0.111  1.0
[/CIF]
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