The compound described by Mg(CoO2)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted MgO5 square pyramids that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(4)O6 octahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-56°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form CoO6 octahedra that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 49-54°. In the second Co site, Co(2) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 49-57°. In the third Co site, Co(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form CoO6 octahedra that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and  an edgeedge with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 52-57°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Co(3) and two equivalent Co(4) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1) and two equivalent Co(3) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(4) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMgCo3 trigonal pyramids that share corners with two equivalent O(4)MgCo3 trigonal pyramids, edges with two equivalent O(7)Mg2Co3 square pyramids, and edges with two equivalent O(6)Mg2Co3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Co(4) and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Co(3), and two equivalent Co(2) atoms to form distorted OMg2Co3 trigonal bipyramids that share corners with two equivalent O(7)Mg2Co3 square pyramids,  an edgeedge with one O(7)Mg2Co3 square pyramid, edges with two equivalent O(6)Mg2Co3 trigonal bipyramids, and edges with two equivalent O(4)MgCo3 trigonal pyramids. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Co(1), and two equivalent Co(4) atoms to form OMg2Co3 square pyramids that share corners with two equivalent O(6)Mg2Co3 trigonal bipyramids, edges with two equivalent O(7)Mg2Co3 square pyramids,  an edgeedge with one O(6)Mg2Co3 trigonal bipyramid, and edges with two equivalent O(4)MgCo3 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg(CoO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.851
_cell_length_b   6.793
_cell_length_c   6.981
_cell_angle_alpha   81.359
_cell_angle_beta   78.221
_cell_angle_gamma   77.894
_symmetry_Int_Tables_number   1
_cell_volume   128.613
_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  0.352  0.122  0.185  1.0
  Co  Co1  1  0.639  0.169  0.564  1.0
  Co  Co2  1  0.153  0.506  0.200  1.0
  Co  Co3  1  0.844  0.489  0.835  1.0
  Co  Co4  1  0.359  0.802  0.493  1.0
  O  O5  1  0.869  0.661  0.614  1.0
  O  O6  1  0.461  0.325  0.765  1.0
  O  O7  1  0.540  0.665  0.268  1.0
  O  O8  1  0.143  0.304  0.422  1.0
  O  O9  1  0.167  0.008  0.670  1.0
  O  O10  1  0.793  0.334  0.091  1.0
  O  O11  1  0.837  0.976  0.361  1.0
  O  O12  1  0.221  0.630  0.940  1.0
[/CIF]
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The compound described by Mg(CoO2)4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted MgO5 square pyramids that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(4)O6 octahedra,  an edgeedge with one Co(4)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-56°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form CoO6 octahedra that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 49-54°. In the second Co site, Co(2) is bonded to one O(4), one O(8), two equivalent O(3), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(2)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, and  a faceface with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 49-57°. In the third Co site, Co(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form CoO6 octahedra that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(2)O6 octahedra, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-54°. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(7) atoms to form CoO6 octahedra that share corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and  an edgeedge with one Mg(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 52-57°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Co(3) and two equivalent Co(4) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1) and two equivalent Co(3) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Co(4) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMgCo3 trigonal pyramids that share corners with two equivalent O(4)MgCo3 trigonal pyramids, edges with two equivalent O(7)Mg2Co3 square pyramids, and edges with two equivalent O(6)Mg2Co3 trigonal bipyramids. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Co(4) and two equivalent Co(1) atoms. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Co(3), and two equivalent Co(2) atoms to form distorted OMg2Co3 trigonal bipyramids that share corners with two equivalent O(7)Mg2Co3 square pyramids,  an edgeedge with one O(7)Mg2Co3 square pyramid, edges with two equivalent O(6)Mg2Co3 trigonal bipyramids, and edges with two equivalent O(4)MgCo3 trigonal pyramids. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Co(1), and two equivalent Co(4) atoms to form OMg2Co3 square pyramids that share corners with two equivalent O(6)Mg2Co3 trigonal bipyramids, edges with two equivalent O(7)Mg2Co3 square pyramids,  an edgeedge with one O(6)Mg2Co3 trigonal bipyramid, and edges with two equivalent O(4)MgCo3 trigonal pyramids. In the eighth O site, O(8) is bonded in a distorted trigonal non-coplanar geometry to one Co(2) and two equivalent Co(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg(CoO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.851
_cell_length_b   6.793
_cell_length_c   6.981
_cell_angle_alpha   81.359
_cell_angle_beta   78.221
_cell_angle_gamma   77.894
_symmetry_Int_Tables_number   1
_cell_volume   128.613
_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  0.352  0.122  0.185  1.0
  Co  Co1  1  0.639  0.169  0.564  1.0
  Co  Co2  1  0.153  0.506  0.200  1.0
  Co  Co3  1  0.844  0.489  0.835  1.0
  Co  Co4  1  0.359  0.802  0.493  1.0
  O  O5  1  0.869  0.661  0.614  1.0
  O  O6  1  0.461  0.325  0.765  1.0
  O  O7  1  0.540  0.665  0.268  1.0
  O  O8  1  0.143  0.304  0.422  1.0
  O  O9  1  0.167  0.008  0.670  1.0
  O  O10  1  0.793  0.334  0.091  1.0
  O  O11  1  0.837  0.976  0.361  1.0
  O  O12  1  0.221  0.630  0.940  1.0
[/CIF]
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