The crystal structure described by MgCd2(FeO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), one O(4), and one O(7) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), one O(6), one O(7), and one O(8) atom to form distorted FeO5 square pyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra,  an edgeedge with one Fe(2)O5 trigonal bipyramid, and edges with two equivalent Fe(3)O5 trigonal bipyramids. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(8) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the third Fe site, Fe(3) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra, edges with two equivalent Fe(1)O5 square pyramids, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and one O(8) atom. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one O(2), one O(3), one O(4), and one O(7) atom to form CdO4 tetrahedra that share corners with two equivalent Fe(1)O5 square pyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids, and corners with two equivalent Fe(3)O5 trigonal bipyramids. In the second Cd site, Cd(2) is bonded to one O(1), one O(5), one O(6), and one O(8) atom to form distorted CdO4 tetrahedra that share corners with three equivalent Fe(1)O5 square pyramids, corners with three equivalent Fe(2)O5 trigonal bipyramids, and corners with three equivalent Fe(3)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one Cd(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(2), one Fe(4), and one Cd(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(4), and one Cd(1) atom. In the fourth O site, O(4) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(1), one Fe(3), and one Cd(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(2), one Fe(3), one Fe(4), and one Cd(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(3), one Fe(4), and one Cd(2) atom. In the seventh O site, O(7) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(1), one Fe(3), and one Cd(1) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(4), and one Cd(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCd2(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.079
_cell_length_b   6.971
_cell_length_c   7.180
_cell_angle_alpha   51.007
_cell_angle_beta   66.807
_cell_angle_gamma   66.121
_symmetry_Int_Tables_number   1
_cell_volume   212.053
_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  0.363  0.412  0.339  1.0
  Cd  Cd1  1  0.103  0.154  0.097  1.0
  Cd  Cd2  1  0.898  0.843  0.909  1.0
  Fe  Fe3  1  0.515  0.947  0.480  1.0
  Fe  Fe4  1  0.954  0.571  0.548  1.0
  Fe  Fe5  1  0.558  0.424  0.948  1.0
  Fe  Fe6  1  0.477  0.535  0.548  1.0
  O  O7  1  0.751  0.721  0.729  1.0
  O  O8  1  0.248  0.299  0.691  1.0
  O  O9  1  0.220  0.742  0.290  1.0
  O  O10  1  0.705  0.283  0.223  1.0
  O  O11  1  0.753  0.274  0.766  1.0
  O  O12  1  0.289  0.697  0.764  1.0
  O  O13  1  0.297  0.240  0.234  1.0
  O  O14  1  0.743  0.733  0.308  1.0
[/CIF]
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The crystal structure described by MgCd2(FeO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(2), one O(3), one O(4), and one O(7) atom. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), one O(6), one O(7), and one O(8) atom to form distorted FeO5 square pyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra,  an edgeedge with one Fe(2)O5 trigonal bipyramid, and edges with two equivalent Fe(3)O5 trigonal bipyramids. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(8) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra,  an edgeedge with one Fe(1)O5 square pyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the third Fe site, Fe(3) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Cd(1)O4 tetrahedra, corners with three equivalent Cd(2)O4 tetrahedra, edges with two equivalent Fe(1)O5 square pyramids, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(5), one O(6), and one O(8) atom. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to one O(2), one O(3), one O(4), and one O(7) atom to form CdO4 tetrahedra that share corners with two equivalent Fe(1)O5 square pyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids, and corners with two equivalent Fe(3)O5 trigonal bipyramids. In the second Cd site, Cd(2) is bonded to one O(1), one O(5), one O(6), and one O(8) atom to form distorted CdO4 tetrahedra that share corners with three equivalent Fe(1)O5 square pyramids, corners with three equivalent Fe(2)O5 trigonal bipyramids, and corners with three equivalent Fe(3)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one Cd(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(2), one Fe(4), and one Cd(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(4), and one Cd(1) atom. In the fourth O site, O(4) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(1), one Fe(3), and one Cd(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(2), one Fe(3), one Fe(4), and one Cd(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(3), one Fe(4), and one Cd(2) atom. In the seventh O site, O(7) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(1), one Fe(3), and one Cd(1) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(4), and one Cd(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCd2(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.079
_cell_length_b   6.971
_cell_length_c   7.180
_cell_angle_alpha   51.007
_cell_angle_beta   66.807
_cell_angle_gamma   66.121
_symmetry_Int_Tables_number   1
_cell_volume   212.053
_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  0.363  0.412  0.339  1.0
  Cd  Cd1  1  0.103  0.154  0.097  1.0
  Cd  Cd2  1  0.898  0.843  0.909  1.0
  Fe  Fe3  1  0.515  0.947  0.480  1.0
  Fe  Fe4  1  0.954  0.571  0.548  1.0
  Fe  Fe5  1  0.558  0.424  0.948  1.0
  Fe  Fe6  1  0.477  0.535  0.548  1.0
  O  O7  1  0.751  0.721  0.729  1.0
  O  O8  1  0.248  0.299  0.691  1.0
  O  O9  1  0.220  0.742  0.290  1.0
  O  O10  1  0.705  0.283  0.223  1.0
  O  O11  1  0.753  0.274  0.766  1.0
  O  O12  1  0.289  0.697  0.764  1.0
  O  O13  1  0.297  0.240  0.234  1.0
  O  O14  1  0.743  0.733  0.308  1.0
[/CIF]
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