The material described by NaMgFe(SeO4)2 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form NaO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, corners with three equivalent Se(2)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. Mg(1) is bonded to one O(2), one O(5), and two equivalent O(1) atoms to form distorted MgO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, corners with two equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Se(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-73°. Fe(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, corners with three equivalent Se(2)O4 tetrahedra, and edges with two equivalent Na(1)O6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(2), one O(5), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-78°. In the second Se site, Se(2) is bonded to one O(4), one O(6), and two equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 20-67°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mg(1), one Fe(1), and one Se(2) atom to form distorted edge-sharing ONaMgFeSe tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Mg(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted 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(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one Se(2) atom. is represented by the CIF card [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.423
_cell_length_b   5.423
_cell_length_c   6.844
_cell_angle_alpha   92.402
_cell_angle_beta   92.402
_cell_angle_gamma   65.002
_symmetry_Int_Tables_number   1
_cell_volume   182.187
_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  0.007  0.007  0.488  1.0
  Mg  Mg1  1  0.360  0.360  0.201  1.0
  Fe  Fe2  1  0.015  0.015  0.960  1.0
  Se  Se3  1  0.354  0.354  0.719  1.0
  Se  Se4  1  0.663  0.663  0.247  1.0
  O  O5  1  0.760  0.318  0.210  1.0
  O  O6  1  0.297  0.297  0.469  1.0
  O  O7  1  0.229  0.702  0.750  1.0
  O  O8  1  0.318  0.760  0.210  1.0
  O  O9  1  0.791  0.791  0.083  1.0
  O  O10  1  0.702  0.229  0.750  1.0
  O  O11  1  0.230  0.230  0.970  1.0
  O  O12  1  0.734  0.734  0.470  1.0
[/CIF]
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The material described by NaMgFe(SeO4)2 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(2), one O(6), two equivalent O(1), and two equivalent O(3) atoms to form NaO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, corners with three equivalent Se(2)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. Mg(1) is bonded to one O(2), one O(5), and two equivalent O(1) atoms to form distorted MgO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, corners with two equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Se(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-73°. Fe(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, corners with three equivalent Se(2)O4 tetrahedra, and edges with two equivalent Na(1)O6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(2), one O(5), and two equivalent O(3) atoms to form SeO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 40-78°. In the second Se site, Se(2) is bonded to one O(4), one O(6), and two equivalent O(1) atoms to form SeO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 20-67°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Mg(1), one Fe(1), and one Se(2) atom to form distorted edge-sharing ONaMgFeSe tetrahedra. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Mg(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted 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(2) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Na(1) and one Se(2) atom. is represented by the CIF card [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.423
_cell_length_b   5.423
_cell_length_c   6.844
_cell_angle_alpha   92.402
_cell_angle_beta   92.402
_cell_angle_gamma   65.002
_symmetry_Int_Tables_number   1
_cell_volume   182.187
_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  0.007  0.007  0.488  1.0
  Mg  Mg1  1  0.360  0.360  0.201  1.0
  Fe  Fe2  1  0.015  0.015  0.960  1.0
  Se  Se3  1  0.354  0.354  0.719  1.0
  Se  Se4  1  0.663  0.663  0.247  1.0
  O  O5  1  0.760  0.318  0.210  1.0
  O  O6  1  0.297  0.297  0.469  1.0
  O  O7  1  0.229  0.702  0.750  1.0
  O  O8  1  0.318  0.760  0.210  1.0
  O  O9  1  0.791  0.791  0.083  1.0
  O  O10  1  0.702  0.229  0.750  1.0
  O  O11  1  0.230  0.230  0.970  1.0
  O  O12  1  0.734  0.734  0.470  1.0
[/CIF]
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