The compound described by MgCo6(O2F)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(1), two equivalent O(2), and one F(1) atom. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(5), two equivalent O(3), one F(1), one F(2), and one F(3) atom to form CoO3F3 octahedra that share corners with three equivalent Co(5)O4F square pyramids,  an edgeedge with one Co(3)O3F3 octahedra, and  an edgeedge with one Co(2)O4F2 octahedra. In the second Co site, Co(2) is bonded to one O(1), one O(5), two equivalent O(2), one F(1), and one F(4) atom to form CoO4F2 octahedra that share corners with three equivalent Co(6)O4F square pyramids,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(3)O3F3 octahedra. In the third Co site, Co(3) is bonded to one O(1), two equivalent O(4), one F(2), one F(3), and one F(4) atom to form CoO3F3 octahedra that share corners with three equivalent Co(5)O4F square pyramids, corners with three equivalent Co(6)O4F square pyramids,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(2)O4F2 octahedra. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one O(5), two equivalent O(2), and two equivalent O(3) atoms. In the fifth Co site, Co(5) is bonded to two equivalent O(3), two equivalent O(4), and one F(2) atom to form CoO4F square pyramids that share corners with three equivalent Co(1)O3F3 octahedra, corners with three equivalent Co(3)O3F3 octahedra, and  an edgeedge with one Co(6)O4F square pyramid. The corner-sharing octahedral tilt angles range from 42-52°. In the sixth Co site, Co(6) is bonded to two equivalent O(2), two equivalent O(4), and one F(4) atom to form distorted CoO4F square pyramids that share corners with three equivalent Co(3)O3F3 octahedra, corners with three equivalent Co(2)O4F2 octahedra, and  an edgeedge with one Co(5)O4F square pyramid. The corner-sharing octahedral tilt angles range from 40-54°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Co(3), one Co(5), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(4) atom. There are four inequivalent F sites. In the first F site, F(3) is bonded in an L-shaped geometry to one Co(1) and one Co(3) atom. In the second F site, F(4) is bonded in a distorted T-shaped geometry to one Co(2), one Co(3), and one Co(6) atom. In the third F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(1), and one Co(2) atom. In the fourth F site, F(2) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo6(O2F)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.096
_cell_length_b   5.096
_cell_length_c   8.822
_cell_angle_alpha   90.733
_cell_angle_beta   89.267
_cell_angle_gamma   105.714
_symmetry_Int_Tables_number   1
_cell_volume   220.502
_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  0.299  0.701  0.327  1.0
  Co  Co1  1  0.992  0.008  0.997  1.0
  Co  Co2  1  0.966  0.034  0.336  1.0
  Co  Co3  1  0.009  0.991  0.663  1.0
  Co  Co4  1  0.596  0.404  0.158  1.0
  Co  Co5  1  0.470  0.530  0.840  1.0
  Co  Co6  1  0.545  0.455  0.515  1.0
  O  O7  1  0.130  0.870  0.483  1.0
  O  O8  1  0.306  0.310  0.333  1.0
  O  O9  1  0.312  0.298  0.999  1.0
  O  O10  1  0.303  0.314  0.672  1.0
  O  O11  1  0.686  0.697  0.672  1.0
  O  O12  1  0.702  0.688  0.999  1.0
  O  O13  1  0.690  0.694  0.333  1.0
  O  O14  1  0.818  0.182  0.171  1.0
  F  F15  1  0.168  0.832  0.156  1.0
  F  F16  1  0.181  0.819  0.826  1.0
  F  F17  1  0.839  0.161  0.832  1.0
  F  F18  1  0.795  0.205  0.506  1.0
[/CIF]
.
The compound described by MgCo6(O2F)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 4-coordinate geometry to one O(1), two equivalent O(2), and one F(1) atom. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(5), two equivalent O(3), one F(1), one F(2), and one F(3) atom to form CoO3F3 octahedra that share corners with three equivalent Co(5)O4F square pyramids,  an edgeedge with one Co(3)O3F3 octahedra, and  an edgeedge with one Co(2)O4F2 octahedra. In the second Co site, Co(2) is bonded to one O(1), one O(5), two equivalent O(2), one F(1), and one F(4) atom to form CoO4F2 octahedra that share corners with three equivalent Co(6)O4F square pyramids,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(3)O3F3 octahedra. In the third Co site, Co(3) is bonded to one O(1), two equivalent O(4), one F(2), one F(3), and one F(4) atom to form CoO3F3 octahedra that share corners with three equivalent Co(5)O4F square pyramids, corners with three equivalent Co(6)O4F square pyramids,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(2)O4F2 octahedra. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one O(5), two equivalent O(2), and two equivalent O(3) atoms. In the fifth Co site, Co(5) is bonded to two equivalent O(3), two equivalent O(4), and one F(2) atom to form CoO4F square pyramids that share corners with three equivalent Co(1)O3F3 octahedra, corners with three equivalent Co(3)O3F3 octahedra, and  an edgeedge with one Co(6)O4F square pyramid. The corner-sharing octahedral tilt angles range from 42-52°. In the sixth Co site, Co(6) is bonded to two equivalent O(2), two equivalent O(4), and one F(4) atom to form distorted CoO4F square pyramids that share corners with three equivalent Co(3)O3F3 octahedra, corners with three equivalent Co(2)O4F2 octahedra, and  an edgeedge with one Co(5)O4F square pyramid. The corner-sharing octahedral tilt angles range from 40-54°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Co(3), one Co(5), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(4) atom. There are four inequivalent F sites. In the first F site, F(3) is bonded in an L-shaped geometry to one Co(1) and one Co(3) atom. In the second F site, F(4) is bonded in a distorted T-shaped geometry to one Co(2), one Co(3), and one Co(6) atom. In the third F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(1), and one Co(2) atom. In the fourth F site, F(2) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo6(O2F)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.096
_cell_length_b   5.096
_cell_length_c   8.822
_cell_angle_alpha   90.733
_cell_angle_beta   89.267
_cell_angle_gamma   105.714
_symmetry_Int_Tables_number   1
_cell_volume   220.502
_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  0.299  0.701  0.327  1.0
  Co  Co1  1  0.992  0.008  0.997  1.0
  Co  Co2  1  0.966  0.034  0.336  1.0
  Co  Co3  1  0.009  0.991  0.663  1.0
  Co  Co4  1  0.596  0.404  0.158  1.0
  Co  Co5  1  0.470  0.530  0.840  1.0
  Co  Co6  1  0.545  0.455  0.515  1.0
  O  O7  1  0.130  0.870  0.483  1.0
  O  O8  1  0.306  0.310  0.333  1.0
  O  O9  1  0.312  0.298  0.999  1.0
  O  O10  1  0.303  0.314  0.672  1.0
  O  O11  1  0.686  0.697  0.672  1.0
  O  O12  1  0.702  0.688  0.999  1.0
  O  O13  1  0.690  0.694  0.333  1.0
  O  O14  1  0.818  0.182  0.171  1.0
  F  F15  1  0.168  0.832  0.156  1.0
  F  F16  1  0.181  0.819  0.826  1.0
  F  F17  1  0.839  0.161  0.832  1.0
  F  F18  1  0.795  0.205  0.506  1.0
[/CIF]
.