The compound described by Mg(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(2)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. 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(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. In the second Co site, Co(2) is bonded to one O(3), one O(8), and two equivalent O(6) atoms to form CoO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(2)O4 tetrahedra, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-62°. 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 distorted CoO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(2)O4 tetrahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-57°. 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(3)O6 octahedra,  a cornercorner with one Co(2)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(4) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), one Co(1), and two equivalent Co(3) atoms to form distorted edge-sharing OMg2Co3 trigonal bipyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Co(2), and one Co(4) atom. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Co(1) atoms. 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 in a distorted T-shaped geometry to one Co(3) and two equivalent Co(2) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Co(1) and two equivalent Co(4) atoms. 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   2.967
_cell_length_b   7.607
_cell_length_c   7.997
_cell_angle_alpha   106.568
_cell_angle_beta   88.236
_cell_angle_gamma   77.964
_symmetry_Int_Tables_number   1
_cell_volume   168.398
_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  0.906  0.461  0.464  1.0
  Co  Co1  1  0.550  0.140  0.525  1.0
  Co  Co2  1  0.439  0.545  0.116  1.0
  Co  Co3  1  0.933  0.574  0.821  1.0
  Co  Co4  1  0.219  0.815  0.530  1.0
  O  O5  1  0.772  0.734  0.643  1.0
  O  O6  1  0.411  0.410  0.645  1.0
  O  O7  1  0.365  0.569  0.353  1.0
  O  O8  1  0.047  0.184  0.394  1.0
  O  O9  1  0.075  0.072  0.649  1.0
  O  O10  1  0.010  0.415  0.999  1.0
  O  O11  1  0.693  0.884  0.410  1.0
  O  O12  1  0.375  0.698  0.962  1.0
[/CIF]
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The compound described by Mg(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent Co(3)O6 octahedra, corners with two equivalent Co(2)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. 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(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. In the second Co site, Co(2) is bonded to one O(3), one O(8), and two equivalent O(6) atoms to form CoO4 tetrahedra that share  a cornercorner with one Co(4)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(2)O4 tetrahedra, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-62°. 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 distorted CoO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(4)O6 octahedra, edges with two equivalent Co(3)O6 octahedra, edges with two equivalent Co(2)O4 tetrahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-57°. 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(3)O6 octahedra,  a cornercorner with one Co(2)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(3), and two equivalent Co(4) atoms. In the second O site, O(2) is bonded to two equivalent Mg(1), one Co(1), and two equivalent Co(3) atoms to form distorted edge-sharing OMg2Co3 trigonal bipyramids. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Co(2), and one Co(4) atom. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Co(1) atoms. 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 in a distorted T-shaped geometry to one Co(3) and two equivalent Co(2) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Co(1) and two equivalent Co(4) atoms. 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   2.967
_cell_length_b   7.607
_cell_length_c   7.997
_cell_angle_alpha   106.568
_cell_angle_beta   88.236
_cell_angle_gamma   77.964
_symmetry_Int_Tables_number   1
_cell_volume   168.398
_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  0.906  0.461  0.464  1.0
  Co  Co1  1  0.550  0.140  0.525  1.0
  Co  Co2  1  0.439  0.545  0.116  1.0
  Co  Co3  1  0.933  0.574  0.821  1.0
  Co  Co4  1  0.219  0.815  0.530  1.0
  O  O5  1  0.772  0.734  0.643  1.0
  O  O6  1  0.411  0.410  0.645  1.0
  O  O7  1  0.365  0.569  0.353  1.0
  O  O8  1  0.047  0.184  0.394  1.0
  O  O9  1  0.075  0.072  0.649  1.0
  O  O10  1  0.010  0.415  0.999  1.0
  O  O11  1  0.693  0.884  0.410  1.0
  O  O12  1  0.375  0.698  0.962  1.0
[/CIF]
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