The compound described by MgFe7(Ni3O8)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with six equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-21°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-20°. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Ni(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-20°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Ni(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Ni(4)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-21°. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Ni site, Ni(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, edges with two equivalent Ni(4)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the third Ni site, Ni(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(4)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fourth Ni site, Ni(4) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. In the fifth Ni site, Ni(5) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom to form OMgFe4 square pyramids that share corners with three equivalent O(7)Fe3Ni3 octahedra, corners with two equivalent O(1)MgFe4 square pyramids, corners with two equivalent O(6)Fe3Ni trigonal pyramids, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra, edges with three equivalent O(5)MgFe3Ni square pyramids,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Fe(3), one Fe(4), one Ni(1), one Ni(2), one Ni(3), and one Ni(4) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(2)Fe2Ni4 octahedra, corners with three equivalent O(8)MgFe2Ni trigonal pyramids, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(1)MgFe4 square pyramid, and  an edgeedge with one O(6)Fe3Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded to one Fe(2), one Fe(3), one Ni(1), one Ni(2), one Ni(3), and one Ni(5) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(3)Fe2Ni4 octahedra, corners with three equivalent O(6)Fe3Ni trigonal pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(1)MgFe4 square pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to one Fe(2), one Fe(4), one Ni(1), one Ni(2), one Ni(4), and one Ni(5) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(4)Fe2Ni4 octahedra, corners with three equivalent O(5)MgFe3Ni square pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(1)MgFe4 square pyramid,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(2), one Fe(4), and one Ni(1) atom to form OMgFe3Ni square pyramids that share corners with three equivalent O(4)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(6)Fe3Ni trigonal pyramids, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra, edges with three equivalent O(1)MgFe4 square pyramids,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedral tilt angles range from 2-13°. In the sixth O site, O(6) is bonded to one Fe(1), one Fe(2), one Fe(3), and one Ni(1) atom to form OFe3Ni trigonal pyramids that share corners with three equivalent O(3)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(1)MgFe4 square pyramids,  a cornercorner with one O(6)Fe3Ni trigonal pyramid, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid, and  an edgeedge with one O(1)MgFe4 square pyramid. The corner-sharing octahedral tilt angles range from 5-16°. In the seventh O site, O(7) is bonded to one Fe(2), one Fe(3), one Fe(4), one Ni(3), one Ni(4), and one Ni(5) atom to form OFe3Ni3 octahedra that share corners with three equivalent O(7)Fe3Ni3 octahedra, corners with three equivalent O(1)MgFe4 square pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the eighth O site, O(8) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Ni(1) atom to form OMgFe2Ni trigonal pyramids that share corners with three equivalent O(2)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(1)MgFe4 square pyramids,  a cornercorner with one O(8)MgFe2Ni trigonal pyramid, corners with two equivalent O(6)Fe3Ni trigonal pyramids,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid, and  an edgeedge with one O(1)MgFe4 square pyramid. The corner-sharing octahedral tilt angles range from 4-15°. is represented by the CIF card [CIF]
data_MgFe7(Ni3O8)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.077
_cell_length_b   6.045
_cell_length_c   10.546
_cell_angle_alpha   108.788
_cell_angle_beta   72.992
_cell_angle_gamma   120.173
_symmetry_Int_Tables_number   1
_cell_volume   313.039
_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  0.812  0.688  0.062  1.0
  Fe  Fe1  1  0.312  0.688  0.062  1.0
  Fe  Fe2  1  0.066  0.968  0.833  1.0
  Fe  Fe3  1  0.560  0.927  0.316  1.0
  Fe  Fe4  1  0.059  0.410  0.295  1.0
  Fe  Fe5  1  0.559  0.407  0.292  1.0
  Fe  Fe6  1  0.566  0.965  0.830  1.0
  Fe  Fe7  1  0.065  0.448  0.809  1.0
  Ni  Ni8  1  0.052  0.924  0.317  1.0
  Ni  Ni9  1  0.312  0.688  0.562  1.0
  Ni  Ni10  1  0.812  0.688  0.562  1.0
  Ni  Ni11  1  0.312  0.188  0.562  1.0
  Ni  Ni12  1  0.812  0.188  0.562  1.0
  Ni  Ni13  1  0.573  0.451  0.808  1.0
  O  O14  1  0.450  0.566  0.197  1.0
  O  O15  1  0.184  0.798  0.439  1.0
  O  O16  1  0.676  0.801  0.442  1.0
  O  O17  1  0.196  0.308  0.440  1.0
  O  O18  1  0.915  0.558  0.195  1.0
  O  O19  1  0.419  0.033  0.210  1.0
  O  O20  1  0.674  0.302  0.440  1.0
  O  O21  1  0.903  0.027  0.211  1.0
  O  O22  1  0.175  0.809  0.928  1.0
  O  O23  1  0.441  0.577  0.686  1.0
  O  O24  1  0.710  0.817  0.930  1.0
  O  O25  1  0.206  0.342  0.915  1.0
  O  O26  1  0.949  0.574  0.683  1.0
  O  O27  1  0.429  0.067  0.685  1.0
  O  O28  1  0.951  0.073  0.685  1.0
  O  O29  1  0.722  0.348  0.914  1.0
[/CIF]
.
The compound described by MgFe7(Ni3O8)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(8) atoms to form MgO6 octahedra that share corners with six equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-21°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-20°. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO6 octahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with three equivalent Ni(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-20°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Ni(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Ni(4)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-21°. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra,  an edgeedge with one Ni(5)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Ni site, Ni(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, edges with two equivalent Ni(4)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the third Ni site, Ni(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(4)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fourth Ni site, Ni(4) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(4)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. In the fifth Ni site, Ni(5) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with six equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom to form OMgFe4 square pyramids that share corners with three equivalent O(7)Fe3Ni3 octahedra, corners with two equivalent O(1)MgFe4 square pyramids, corners with two equivalent O(6)Fe3Ni trigonal pyramids, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra, edges with three equivalent O(5)MgFe3Ni square pyramids,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedral tilt angles range from 0-13°. In the second O site, O(2) is bonded to one Fe(3), one Fe(4), one Ni(1), one Ni(2), one Ni(3), and one Ni(4) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(2)Fe2Ni4 octahedra, corners with three equivalent O(8)MgFe2Ni trigonal pyramids, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(1)MgFe4 square pyramid, and  an edgeedge with one O(6)Fe3Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded to one Fe(2), one Fe(3), one Ni(1), one Ni(2), one Ni(3), and one Ni(5) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(3)Fe2Ni4 octahedra, corners with three equivalent O(6)Fe3Ni trigonal pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(1)MgFe4 square pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to one Fe(2), one Fe(4), one Ni(1), one Ni(2), one Ni(4), and one Ni(5) atom to form OFe2Ni4 octahedra that share corners with three equivalent O(4)Fe2Ni4 octahedra, corners with three equivalent O(5)MgFe3Ni square pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(7)Fe3Ni3 octahedra,  an edgeedge with one O(1)MgFe4 square pyramid,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(2), one Fe(4), and one Ni(1) atom to form OMgFe3Ni square pyramids that share corners with three equivalent O(4)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(6)Fe3Ni trigonal pyramids, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra, edges with three equivalent O(1)MgFe4 square pyramids,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedral tilt angles range from 2-13°. In the sixth O site, O(6) is bonded to one Fe(1), one Fe(2), one Fe(3), and one Ni(1) atom to form OFe3Ni trigonal pyramids that share corners with three equivalent O(3)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(1)MgFe4 square pyramids,  a cornercorner with one O(6)Fe3Ni trigonal pyramid, corners with two equivalent O(8)MgFe2Ni trigonal pyramids,  an edgeedge with one O(2)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid, and  an edgeedge with one O(1)MgFe4 square pyramid. The corner-sharing octahedral tilt angles range from 5-16°. In the seventh O site, O(7) is bonded to one Fe(2), one Fe(3), one Fe(4), one Ni(3), one Ni(4), and one Ni(5) atom to form OFe3Ni3 octahedra that share corners with three equivalent O(7)Fe3Ni3 octahedra, corners with three equivalent O(1)MgFe4 square pyramids, edges with three equivalent O(2)Fe2Ni4 octahedra, edges with three equivalent O(3)Fe2Ni4 octahedra, edges with three equivalent O(4)Fe2Ni4 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid,  an edgeedge with one O(6)Fe3Ni trigonal pyramid, and  an edgeedge with one O(8)MgFe2Ni trigonal pyramid. The corner-sharing octahedra are not tilted. In the eighth O site, O(8) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Ni(1) atom to form OMgFe2Ni trigonal pyramids that share corners with three equivalent O(2)Fe2Ni4 octahedra, corners with two equivalent O(5)MgFe3Ni square pyramids, corners with two equivalent O(1)MgFe4 square pyramids,  a cornercorner with one O(8)MgFe2Ni trigonal pyramid, corners with two equivalent O(6)Fe3Ni trigonal pyramids,  an edgeedge with one O(3)Fe2Ni4 octahedra,  an edgeedge with one O(4)Fe2Ni4 octahedra,  an edgeedge with one O(7)Fe3Ni3 octahedra,  an edgeedge with one O(5)MgFe3Ni square pyramid, and  an edgeedge with one O(1)MgFe4 square pyramid. The corner-sharing octahedral tilt angles range from 4-15°. is represented by the CIF card [CIF]
data_MgFe7(Ni3O8)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.077
_cell_length_b   6.045
_cell_length_c   10.546
_cell_angle_alpha   108.788
_cell_angle_beta   72.992
_cell_angle_gamma   120.173
_symmetry_Int_Tables_number   1
_cell_volume   313.039
_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  0.812  0.688  0.062  1.0
  Fe  Fe1  1  0.312  0.688  0.062  1.0
  Fe  Fe2  1  0.066  0.968  0.833  1.0
  Fe  Fe3  1  0.560  0.927  0.316  1.0
  Fe  Fe4  1  0.059  0.410  0.295  1.0
  Fe  Fe5  1  0.559  0.407  0.292  1.0
  Fe  Fe6  1  0.566  0.965  0.830  1.0
  Fe  Fe7  1  0.065  0.448  0.809  1.0
  Ni  Ni8  1  0.052  0.924  0.317  1.0
  Ni  Ni9  1  0.312  0.688  0.562  1.0
  Ni  Ni10  1  0.812  0.688  0.562  1.0
  Ni  Ni11  1  0.312  0.188  0.562  1.0
  Ni  Ni12  1  0.812  0.188  0.562  1.0
  Ni  Ni13  1  0.573  0.451  0.808  1.0
  O  O14  1  0.450  0.566  0.197  1.0
  O  O15  1  0.184  0.798  0.439  1.0
  O  O16  1  0.676  0.801  0.442  1.0
  O  O17  1  0.196  0.308  0.440  1.0
  O  O18  1  0.915  0.558  0.195  1.0
  O  O19  1  0.419  0.033  0.210  1.0
  O  O20  1  0.674  0.302  0.440  1.0
  O  O21  1  0.903  0.027  0.211  1.0
  O  O22  1  0.175  0.809  0.928  1.0
  O  O23  1  0.441  0.577  0.686  1.0
  O  O24  1  0.710  0.817  0.930  1.0
  O  O25  1  0.206  0.342  0.915  1.0
  O  O26  1  0.949  0.574  0.683  1.0
  O  O27  1  0.429  0.067  0.685  1.0
  O  O28  1  0.951  0.073  0.685  1.0
  O  O29  1  0.722  0.348  0.914  1.0
[/CIF]
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