The material described by Mg(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(8) atoms to form MgO5 square pyramids that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-54°. 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, 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 50-55°. 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, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. 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 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 49-55°. 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, 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°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(3), and two equivalent Co(4) atoms to form OMgCo3 trigonal pyramids that share corners with two equivalent O(1)MgCo3 trigonal pyramids and edges with two equivalent O(5)Mg2Co3 square pyramids. 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 in a trigonal planar geometry to one Co(2) and two equivalent Co(1) atoms. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Co(4), and two equivalent Co(1) atoms to form OMg2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(1)MgCo3 trigonal pyramids. In the sixth O site, O(6) is bonded in a trigonal non-coplanar 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 5-coordinate geometry to two equivalent Mg(1), one Co(2), and two equivalent Co(3) atoms. is represented by the CIF card [CIF]
data_Mg(CoO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.953
_cell_length_b   6.933
_cell_length_c   7.023
_cell_angle_alpha   82.318
_cell_angle_beta   77.163
_cell_angle_gamma   77.095
_symmetry_Int_Tables_number   1
_cell_volume   136.124
_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  0.644  0.880  0.854  1.0
  Co  Co1  1  0.630  0.196  0.529  1.0
  Co  Co2  1  0.150  0.515  0.197  1.0
  Co  Co3  1  0.828  0.492  0.825  1.0
  Co  Co4  1  0.354  0.826  0.480  1.0
  O  O5  1  0.849  0.697  0.616  1.0
  O  O6  1  0.439  0.350  0.737  1.0
  O  O7  1  0.531  0.659  0.287  1.0
  O  O8  1  0.129  0.327  0.402  1.0
  O  O9  1  0.157  0.017  0.679  1.0
  O  O10  1  0.776  0.382  0.084  1.0
  O  O11  1  0.836  0.978  0.368  1.0
  O  O12  1  0.200  0.684  0.954  1.0
[/CIF]
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The material described by Mg(CoO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(8) atoms to form MgO5 square pyramids that share corners with two equivalent Co(1)O6 octahedra, corners with two equivalent Co(2)O6 octahedra, corners with two equivalent Co(3)O6 octahedra,  an edgeedge with one Co(1)O6 octahedra, edges with two equivalent Co(4)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and  a faceface with one Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-54°. 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, 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 50-55°. 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, and edges with two equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. 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 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 49-55°. 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, 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°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(3), and two equivalent Co(4) atoms to form OMgCo3 trigonal pyramids that share corners with two equivalent O(1)MgCo3 trigonal pyramids and edges with two equivalent O(5)Mg2Co3 square pyramids. 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 in a trigonal planar geometry to one Co(2) and two equivalent Co(1) atoms. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Co(4), and two equivalent Co(1) atoms to form OMg2Co3 square pyramids that share edges with two equivalent O(5)Mg2Co3 square pyramids and edges with two equivalent O(1)MgCo3 trigonal pyramids. In the sixth O site, O(6) is bonded in a trigonal non-coplanar 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 5-coordinate geometry to two equivalent Mg(1), one Co(2), and two equivalent Co(3) atoms. is represented by the CIF card [CIF]
data_Mg(CoO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.953
_cell_length_b   6.933
_cell_length_c   7.023
_cell_angle_alpha   82.318
_cell_angle_beta   77.163
_cell_angle_gamma   77.095
_symmetry_Int_Tables_number   1
_cell_volume   136.124
_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  0.644  0.880  0.854  1.0
  Co  Co1  1  0.630  0.196  0.529  1.0
  Co  Co2  1  0.150  0.515  0.197  1.0
  Co  Co3  1  0.828  0.492  0.825  1.0
  Co  Co4  1  0.354  0.826  0.480  1.0
  O  O5  1  0.849  0.697  0.616  1.0
  O  O6  1  0.439  0.350  0.737  1.0
  O  O7  1  0.531  0.659  0.287  1.0
  O  O8  1  0.129  0.327  0.402  1.0
  O  O9  1  0.157  0.017  0.679  1.0
  O  O10  1  0.776  0.382  0.084  1.0
  O  O11  1  0.836  0.978  0.368  1.0
  O  O12  1  0.200  0.684  0.954  1.0
[/CIF]
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