The crystal structure described by NaMgFe(SeO4)2 crystallizes in the monoclinic C2 space group. Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(2) atoms. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-58°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Mg(1), and one Se(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Na(1), one Fe(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.208
_cell_length_b   5.208
_cell_length_c   7.316
_cell_angle_alpha   89.847
_cell_angle_beta   89.847
_cell_angle_gamma   73.998
_symmetry_Int_Tables_number   1
_cell_volume   190.717
_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
  Na  Na0  1  0.175  0.825  0.500  1.0
  Mg  Mg1  1  0.688  0.312  0.500  1.0
  Fe  Fe2  1  0.983  0.017  0.000  1.0
  Se  Se3  1  0.360  0.401  0.802  1.0
  Se  Se4  1  0.599  0.640  0.198  1.0
  O  O5  1  0.750  0.276  0.226  1.0
  O  O6  1  0.295  0.324  0.577  1.0
  O  O7  1  0.212  0.742  0.801  1.0
  O  O8  1  0.258  0.788  0.199  1.0
  O  O9  1  0.747  0.767  0.030  1.0
  O  O10  1  0.724  0.250  0.774  1.0
  O  O11  1  0.233  0.253  0.970  1.0
  O  O12  1  0.676  0.705  0.423  1.0
[/CIF]
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The crystal structure described by NaMgFe(SeO4)2 crystallizes in the monoclinic C2 space group. Na(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(2) atoms. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Fe(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 41-58°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na(1), one Mg(1), and one Se(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Na(1), one Fe(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one Se(1) atom. is represented by the CIF card [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.208
_cell_length_b   5.208
_cell_length_c   7.316
_cell_angle_alpha   89.847
_cell_angle_beta   89.847
_cell_angle_gamma   73.998
_symmetry_Int_Tables_number   1
_cell_volume   190.717
_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
  Na  Na0  1  0.175  0.825  0.500  1.0
  Mg  Mg1  1  0.688  0.312  0.500  1.0
  Fe  Fe2  1  0.983  0.017  0.000  1.0
  Se  Se3  1  0.360  0.401  0.802  1.0
  Se  Se4  1  0.599  0.640  0.198  1.0
  O  O5  1  0.750  0.276  0.226  1.0
  O  O6  1  0.295  0.324  0.577  1.0
  O  O7  1  0.212  0.742  0.801  1.0
  O  O8  1  0.258  0.788  0.199  1.0
  O  O9  1  0.747  0.767  0.030  1.0
  O  O10  1  0.724  0.250  0.774  1.0
  O  O11  1  0.233  0.253  0.970  1.0
  O  O12  1  0.676  0.705  0.423  1.0
[/CIF]
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