The material described by NaMgFe5O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded in a 5-coordinate geometry to one O(5), two equivalent O(1), and two equivalent O(4) atoms. Mg(1) is bonded to one O(2), one O(6), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Fe(2)O4 tetrahedra. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Fe site, Fe(2) is bonded to one O(3), one O(5), and two equivalent O(4) atoms to form FeO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. In the third Fe site, Fe(3) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(4) atoms. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(2), one O(5), one O(6), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Fe(1), one Fe(3), and one Fe(4) atom to form ONaFe3 tetrahedra that share  a cornercorner with one O(1)NaFe3 tetrahedra,  a cornercorner with one O(5)NaFe4 trigonal bipyramid, corners with five equivalent O(4)NaMgFe3 trigonal bipyramids,  an edgeedge with one O(1)NaFe3 tetrahedra, and  an edgeedge with one O(5)NaFe4 trigonal bipyramid. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(4), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Fe(2), one Fe(3), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form distorted ONaMgFe3 trigonal bipyramids that share corners with five equivalent O(1)NaFe3 tetrahedra,  a cornercorner with one O(5)NaFe4 trigonal bipyramid,  a cornercorner with one O(4)NaMgFe3 trigonal bipyramid,  an edgeedge with one O(5)NaFe4 trigonal bipyramid, and  a faceface with one O(4)NaMgFe3 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Na(1), one Fe(2), one Fe(4), and two equivalent Fe(1) atoms to form ONaFe4 trigonal bipyramids that share corners with two equivalent O(1)NaFe3 tetrahedra, corners with two equivalent O(4)NaMgFe3 trigonal bipyramids, edges with two equivalent O(1)NaFe3 tetrahedra, and edges with two equivalent O(4)NaMgFe3 trigonal bipyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(4), and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgFe5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.356
_cell_length_b   6.204
_cell_length_c   6.199
_cell_angle_alpha   61.656
_cell_angle_beta   90.376
_cell_angle_gamma   120.873
_symmetry_Int_Tables_number   1
_cell_volume   175.335
_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  0.697  0.780  0.697  1.0
  Mg  Mg1  1  0.461  0.522  0.461  1.0
  Fe  Fe2  1  0.585  0.228  0.168  1.0
  Fe  Fe3  1  0.041  0.978  0.041  1.0
  Fe  Fe4  1  0.682  0.227  0.682  1.0
  Fe  Fe5  1  0.147  0.530  0.147  1.0
  Fe  Fe6  1  0.168  0.810  0.585  1.0
  O  O7  1  0.806  0.225  0.399  1.0
  O  O8  1  0.332  0.258  0.332  1.0
  O  O9  1  0.900  0.220  0.900  1.0
  O  O10  1  0.846  0.696  0.419  1.0
  O  O11  1  0.930  0.706  0.930  1.0
  O  O12  1  0.419  0.269  0.846  1.0
  O  O13  1  0.338  0.775  0.338  1.0
  O  O14  1  0.399  0.818  0.806  1.0
[/CIF]
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The material described by NaMgFe5O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded in a 5-coordinate geometry to one O(5), two equivalent O(1), and two equivalent O(4) atoms. Mg(1) is bonded to one O(2), one O(6), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Fe(2)O4 tetrahedra. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Fe site, Fe(2) is bonded to one O(3), one O(5), and two equivalent O(4) atoms to form FeO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra. In the third Fe site, Fe(3) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(4) atoms. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(2), one O(5), one O(6), and two equivalent O(1) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Fe(1), one Fe(3), and one Fe(4) atom to form ONaFe3 tetrahedra that share  a cornercorner with one O(1)NaFe3 tetrahedra,  a cornercorner with one O(5)NaFe4 trigonal bipyramid, corners with five equivalent O(4)NaMgFe3 trigonal bipyramids,  an edgeedge with one O(1)NaFe3 tetrahedra, and  an edgeedge with one O(5)NaFe4 trigonal bipyramid. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(4), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Fe(2), one Fe(3), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded to one Na(1), one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form distorted ONaMgFe3 trigonal bipyramids that share corners with five equivalent O(1)NaFe3 tetrahedra,  a cornercorner with one O(5)NaFe4 trigonal bipyramid,  a cornercorner with one O(4)NaMgFe3 trigonal bipyramid,  an edgeedge with one O(5)NaFe4 trigonal bipyramid, and  a faceface with one O(4)NaMgFe3 trigonal bipyramid. In the fifth O site, O(5) is bonded to one Na(1), one Fe(2), one Fe(4), and two equivalent Fe(1) atoms to form ONaFe4 trigonal bipyramids that share corners with two equivalent O(1)NaFe3 tetrahedra, corners with two equivalent O(4)NaMgFe3 trigonal bipyramids, edges with two equivalent O(1)NaFe3 tetrahedra, and edges with two equivalent O(4)NaMgFe3 trigonal bipyramids. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(4), and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaMgFe5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.356
_cell_length_b   6.204
_cell_length_c   6.199
_cell_angle_alpha   61.656
_cell_angle_beta   90.376
_cell_angle_gamma   120.873
_symmetry_Int_Tables_number   1
_cell_volume   175.335
_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  0.697  0.780  0.697  1.0
  Mg  Mg1  1  0.461  0.522  0.461  1.0
  Fe  Fe2  1  0.585  0.228  0.168  1.0
  Fe  Fe3  1  0.041  0.978  0.041  1.0
  Fe  Fe4  1  0.682  0.227  0.682  1.0
  Fe  Fe5  1  0.147  0.530  0.147  1.0
  Fe  Fe6  1  0.168  0.810  0.585  1.0
  O  O7  1  0.806  0.225  0.399  1.0
  O  O8  1  0.332  0.258  0.332  1.0
  O  O9  1  0.900  0.220  0.900  1.0
  O  O10  1  0.846  0.696  0.419  1.0
  O  O11  1  0.930  0.706  0.930  1.0
  O  O12  1  0.419  0.269  0.846  1.0
  O  O13  1  0.338  0.775  0.338  1.0
  O  O14  1  0.399  0.818  0.806  1.0
[/CIF]
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