The material structure described by MgFe2(NiS2)4 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 8-coordinate geometry to two equivalent Fe(1) and six equivalent S(2) atoms. Fe(1) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), and three equivalent S(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent S(2) atoms to form edge-sharing NiS6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form edge-sharing NiS6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1) and three equivalent Ni(2) atoms. In the second S site, S(2) is bonded to one Mg(1), one Fe(1), one Ni(1), and two equivalent Ni(2) atoms to form a mixture of corner and edge-sharing SMgFeNi3 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe2(NiS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.940
_cell_length_b   6.940
_cell_length_c   6.940
_cell_angle_alpha   56.915
_cell_angle_beta   56.915
_cell_angle_gamma   56.915
_symmetry_Int_Tables_number   1
_cell_volume   219.529
_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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.139  0.139  0.139  1.0
  Fe  Fe2  1  0.861  0.861  0.861  1.0
  Ni  Ni3  1  0.500  0.500  0.500  1.0
  Ni  Ni4  1  0.500  0.500  0.000  1.0
  Ni  Ni5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.500  1.0
  S  S7  1  0.262  0.262  0.262  1.0
  S  S8  1  0.739  0.739  0.260  1.0
  S  S9  1  0.260  0.739  0.739  1.0
  S  S10  1  0.739  0.260  0.739  1.0
  S  S11  1  0.740  0.261  0.261  1.0
  S  S12  1  0.261  0.740  0.261  1.0
  S  S13  1  0.261  0.261  0.740  1.0
  S  S14  1  0.738  0.738  0.738  1.0
[/CIF]
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The material structure described by MgFe2(NiS2)4 crystallizes in the trigonal R-3m space group. Mg(1) is bonded in a 8-coordinate geometry to two equivalent Fe(1) and six equivalent S(2) atoms. Fe(1) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), and three equivalent S(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent S(2) atoms to form edge-sharing NiS6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form edge-sharing NiS6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1) and three equivalent Ni(2) atoms. In the second S site, S(2) is bonded to one Mg(1), one Fe(1), one Ni(1), and two equivalent Ni(2) atoms to form a mixture of corner and edge-sharing SMgFeNi3 square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe2(NiS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.940
_cell_length_b   6.940
_cell_length_c   6.940
_cell_angle_alpha   56.915
_cell_angle_beta   56.915
_cell_angle_gamma   56.915
_symmetry_Int_Tables_number   1
_cell_volume   219.529
_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  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.139  0.139  0.139  1.0
  Fe  Fe2  1  0.861  0.861  0.861  1.0
  Ni  Ni3  1  0.500  0.500  0.500  1.0
  Ni  Ni4  1  0.500  0.500  0.000  1.0
  Ni  Ni5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.500  1.0
  S  S7  1  0.262  0.262  0.262  1.0
  S  S8  1  0.739  0.739  0.260  1.0
  S  S9  1  0.260  0.739  0.739  1.0
  S  S10  1  0.739  0.260  0.739  1.0
  S  S11  1  0.740  0.261  0.261  1.0
  S  S12  1  0.261  0.740  0.261  1.0
  S  S13  1  0.261  0.261  0.740  1.0
  S  S14  1  0.738  0.738  0.738  1.0
[/CIF]
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