The compound described by K2Mg(CoO2)2 crystallizes in the monoclinic Cm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. Mg(1) is bonded to one O(1), one O(3), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Co(1)O4 trigonal pyramid, and edges with two equivalent Co(1)O4 trigonal pyramids. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form distorted CoO4 trigonal pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra, corners with two equivalent Co(1)O4 trigonal pyramids,  an edgeedge with one Co(2)O4 tetrahedra, and edges with two equivalent Mg(1)O4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with three equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Co(1)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one Mg(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), and two equivalent Co(2) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent K(1), three equivalent K(2), one Mg(1), and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Mg(1), one Co(1), and one Co(2) atom. is represented by the CIF file [CIF]
data_K2Mg(CoO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.820
_cell_length_b   5.821
_cell_length_c   8.640
_cell_angle_alpha   59.221
_cell_angle_beta   120.780
_cell_angle_gamma   147.029
_symmetry_Int_Tables_number   1
_cell_volume   134.725
_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
  K  K0  1  0.174  0.826  0.632  1.0
  K  K1  1  0.841  0.161  0.396  1.0
  Mg  Mg2  1  0.322  0.679  0.053  1.0
  Co  Co3  1  0.049  0.952  0.191  1.0
  Co  Co4  1  0.987  0.015  0.841  1.0
  O  O5  1  0.168  0.833  0.094  1.0
  O  O6  1  0.445  0.557  0.691  1.0
  O  O7  1  0.521  0.481  0.300  1.0
  O  O8  1  0.848  0.153  0.945  1.0
[/CIF]
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The compound described by K2Mg(CoO2)2 crystallizes in the monoclinic Cm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(2), and three equivalent O(3) atoms. Mg(1) is bonded to one O(1), one O(3), and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra, corners with three equivalent Co(2)O4 tetrahedra,  a cornercorner with one Co(1)O4 trigonal pyramid, and edges with two equivalent Co(1)O4 trigonal pyramids. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form distorted CoO4 trigonal pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra, corners with two equivalent Co(1)O4 trigonal pyramids,  an edgeedge with one Co(2)O4 tetrahedra, and edges with two equivalent Mg(1)O4 tetrahedra. In the second Co site, Co(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O4 tetrahedra, corners with three equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Co(1)O4 trigonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one Mg(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), and two equivalent Co(2) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent K(1), three equivalent K(2), one Mg(1), and two equivalent Co(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent Mg(1), one Co(1), and one Co(2) atom. is represented by the CIF file [CIF]
data_K2Mg(CoO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.820
_cell_length_b   5.821
_cell_length_c   8.640
_cell_angle_alpha   59.221
_cell_angle_beta   120.780
_cell_angle_gamma   147.029
_symmetry_Int_Tables_number   1
_cell_volume   134.725
_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
  K  K0  1  0.174  0.826  0.632  1.0
  K  K1  1  0.841  0.161  0.396  1.0
  Mg  Mg2  1  0.322  0.679  0.053  1.0
  Co  Co3  1  0.049  0.952  0.191  1.0
  Co  Co4  1  0.987  0.015  0.841  1.0
  O  O5  1  0.168  0.833  0.094  1.0
  O  O6  1  0.445  0.557  0.691  1.0
  O  O7  1  0.521  0.481  0.300  1.0
  O  O8  1  0.848  0.153  0.945  1.0
[/CIF]
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