The structure described by MgCu2(O2F)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with three equivalent Cu(2)O3F3 octahedra, corners with four equivalent Cu(1)O3F3 octahedra,  a cornercorner with one O(2)MgCu2O tetrahedra,  an edgeedge with one Cu(2)O3F3 octahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-57°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(4), two equivalent O(2), one F(1), and two equivalent F(2) atoms to form CuO3F3 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Cu(2)O3F3 octahedra, and edges with two equivalent Cu(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. In the second Cu site, Cu(2) is bonded to one O(3), two equivalent O(1), one F(2), and two equivalent F(1) atoms to form distorted CuO3F3 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with four equivalent Cu(1)O3F3 octahedra,  a cornercorner with one O(2)MgCu2O tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Cu(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 7-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Cu(2) atoms. In the second O site, O(2) is bonded to one Mg(1), two equivalent Cu(1), and one O(3) atom to form OMgCu2O tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cu(2)O3F3 octahedra, and corners with two equivalent O(2)MgCu2O tetrahedra. The corner-sharing octahedral tilt angles range from 66-76°. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(2), and one O(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one Cu(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Cu(1) and two equivalent Cu(2) atoms. In the second F site, F(2) is bonded in a distorted trigonal planar geometry to one Cu(2) and two equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_MgCu2(O2F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.029
_cell_length_b   5.153
_cell_length_c   6.734
_cell_angle_alpha   85.183
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   104.747
_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  0.500  0.008  0.493  1.0
  Cu  Cu1  1  0.000  0.674  0.168  1.0
  Cu  Cu2  1  0.500  0.227  0.840  1.0
  O  O3  1  0.000  0.106  0.687  1.0
  O  O4  1  0.500  0.474  0.385  1.0
  O  O5  1  0.500  0.564  0.561  1.0
  O  O6  1  0.000  0.932  0.330  1.0
  F  F7  1  0.000  0.382  0.003  1.0
  F  F8  1  0.500  0.834  0.001  1.0
[/CIF]
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The structure described by MgCu2(O2F)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with three equivalent Cu(2)O3F3 octahedra, corners with four equivalent Cu(1)O3F3 octahedra,  a cornercorner with one O(2)MgCu2O tetrahedra,  an edgeedge with one Cu(2)O3F3 octahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-57°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(4), two equivalent O(2), one F(1), and two equivalent F(2) atoms to form CuO3F3 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Cu(2)O3F3 octahedra, and edges with two equivalent Cu(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 49-57°. In the second Cu site, Cu(2) is bonded to one O(3), two equivalent O(1), one F(2), and two equivalent F(1) atoms to form distorted CuO3F3 octahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with four equivalent Cu(1)O3F3 octahedra,  a cornercorner with one O(2)MgCu2O tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Cu(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 7-54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Cu(2) atoms. In the second O site, O(2) is bonded to one Mg(1), two equivalent Cu(1), and one O(3) atom to form OMgCu2O tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cu(2)O3F3 octahedra, and corners with two equivalent O(2)MgCu2O tetrahedra. The corner-sharing octahedral tilt angles range from 66-76°. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cu(2), and one O(2) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Mg(1) and one Cu(1) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Cu(1) and two equivalent Cu(2) atoms. In the second F site, F(2) is bonded in a distorted trigonal planar geometry to one Cu(2) and two equivalent Cu(1) atoms. is represented by the CIF file [CIF]
data_MgCu2(O2F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.029
_cell_length_b   5.153
_cell_length_c   6.734
_cell_angle_alpha   85.183
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   104.747
_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  0.500  0.008  0.493  1.0
  Cu  Cu1  1  0.000  0.674  0.168  1.0
  Cu  Cu2  1  0.500  0.227  0.840  1.0
  O  O3  1  0.000  0.106  0.687  1.0
  O  O4  1  0.500  0.474  0.385  1.0
  O  O5  1  0.500  0.564  0.561  1.0
  O  O6  1  0.000  0.932  0.330  1.0
  F  F7  1  0.000  0.382  0.003  1.0
  F  F8  1  0.500  0.834  0.001  1.0
[/CIF]
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