The structure described by NaMgFe(SeO4)2 crystallizes in the triclinic P1 space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form MgO5 trigonal bipyramids that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Se(2)O4 tetrahedra, corners with two equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Se(2)O4 tetrahedra. Fe(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share corners with two equivalent Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O5 square pyramids and corners with two equivalent Mg(1)O5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form SeO4 tetrahedra that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Mg(1), and one Se(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar 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 3-coordinate geometry to one Na(1), one Mg(1), one Fe(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Mg(1), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.271
_cell_length_b   5.347
_cell_length_c   7.018
_cell_angle_alpha   88.143
_cell_angle_beta   92.706
_cell_angle_gamma   67.854
_symmetry_Int_Tables_number   1
_cell_volume   182.741
_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  0.006  0.991  0.525  1.0
  Mg  Mg1  1  0.389  0.272  0.286  1.0
  Fe  Fe2  1  0.007  0.974  0.980  1.0
  Se  Se3  1  0.347  0.350  0.775  1.0
  Se  Se4  1  0.627  0.664  0.206  1.0
  O  O5  1  0.765  0.328  0.272  1.0
  O  O6  1  0.241  0.309  0.544  1.0
  O  O7  1  0.238  0.696  0.779  1.0
  O  O8  1  0.292  0.689  0.202  1.0
  O  O9  1  0.764  0.722  0.011  1.0
  O  O10  1  0.701  0.225  0.778  1.0
  O  O11  1  0.246  0.175  0.044  1.0
  O  O12  1  0.654  0.867  0.376  1.0
[/CIF]
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The structure described by NaMgFe(SeO4)2 crystallizes in the triclinic P1 space group. Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(8) atom. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(7), and one O(8) atom to form MgO5 trigonal bipyramids that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Se(2)O4 tetrahedra, corners with two equivalent Se(1)O4 tetrahedra, and  an edgeedge with one Se(2)O4 tetrahedra. Fe(1) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share corners with two equivalent Se(2)O4 tetrahedra, corners with three equivalent Se(1)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form SeO4 tetrahedra that share corners with three equivalent Fe(1)O5 square pyramids and corners with two equivalent Mg(1)O5 trigonal bipyramids. In the second Se site, Se(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form SeO4 tetrahedra that share corners with two equivalent Fe(1)O5 square pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Na(1), one Mg(1), and one Se(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar 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 3-coordinate geometry to one Na(1), one Mg(1), one Fe(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Na(1), one Fe(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Fe(1), and one Se(1) atom. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Mg(1), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.271
_cell_length_b   5.347
_cell_length_c   7.018
_cell_angle_alpha   88.143
_cell_angle_beta   92.706
_cell_angle_gamma   67.854
_symmetry_Int_Tables_number   1
_cell_volume   182.741
_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  0.006  0.991  0.525  1.0
  Mg  Mg1  1  0.389  0.272  0.286  1.0
  Fe  Fe2  1  0.007  0.974  0.980  1.0
  Se  Se3  1  0.347  0.350  0.775  1.0
  Se  Se4  1  0.627  0.664  0.206  1.0
  O  O5  1  0.765  0.328  0.272  1.0
  O  O6  1  0.241  0.309  0.544  1.0
  O  O7  1  0.238  0.696  0.779  1.0
  O  O8  1  0.292  0.689  0.202  1.0
  O  O9  1  0.764  0.722  0.011  1.0
  O  O10  1  0.701  0.225  0.778  1.0
  O  O11  1  0.246  0.175  0.044  1.0
  O  O12  1  0.654  0.867  0.376  1.0
[/CIF]
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