The compound described by MgCo4O9 crystallizes in the monoclinic Pc space group. Mg(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(4), one O(7), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. In the second Co site, Co(2) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), one O(7), and one O(9) atom. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(6), one O(7), and one O(8) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(1), one O(2), one O(6), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(2), one Co(3), and one Co(4) atom to form a mixture of distorted corner and edge-sharing OCo4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(4) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(3), and one Co(4) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), and one Co(3) atom to form a mixture of distorted corner and edge-sharing OMgCo3 tetrahedra. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(3), and one Co(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Co(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.902
_cell_length_b   8.159
_cell_length_c   8.188
_cell_angle_alpha   89.705
_cell_angle_beta   90.004
_cell_angle_gamma   89.996
_symmetry_Int_Tables_number   1
_cell_volume   327.428
_cell_formula_units_Z   2
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  0.148  0.247  0.245  1.0
  Mg  Mg1  1  0.852  0.747  0.745  1.0
  Co  Co2  1  0.615  0.534  0.339  1.0
  Co  Co3  1  0.387  0.839  0.467  1.0
  Co  Co4  1  0.613  0.339  0.967  1.0
  Co  Co5  1  0.385  0.034  0.839  1.0
  Co  Co6  1  0.615  0.966  0.162  1.0
  Co  Co7  1  0.620  0.163  0.535  1.0
  Co  Co8  1  0.385  0.466  0.662  1.0
  Co  Co9  1  0.380  0.663  0.035  1.0
  O  O10  1  0.491  0.750  0.250  1.0
  O  O11  1  0.509  0.250  0.750  1.0
  O  O12  1  0.058  0.684  0.977  1.0
  O  O13  1  0.062  0.521  0.684  1.0
  O  O14  1  0.064  0.976  0.815  1.0
  O  O15  1  0.063  0.817  0.521  1.0
  O  O16  1  0.937  0.317  0.021  1.0
  O  O17  1  0.936  0.476  0.315  1.0
  O  O18  1  0.938  0.021  0.184  1.0
  O  O19  1  0.942  0.184  0.477  1.0
  O  O20  1  0.448  0.046  0.355  1.0
  O  O21  1  0.427  0.146  0.045  1.0
  O  O22  1  0.432  0.355  0.458  1.0
  O  O23  1  0.440  0.455  0.147  1.0
  O  O24  1  0.552  0.546  0.855  1.0
  O  O25  1  0.568  0.855  0.958  1.0
  O  O26  1  0.573  0.646  0.545  1.0
  O  O27  1  0.560  0.955  0.647  1.0
[/CIF]
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The compound described by MgCo4O9 crystallizes in the monoclinic Pc space group. Mg(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(4), one O(7), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. In the second Co site, Co(2) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), one O(7), and one O(9) atom. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(6), one O(7), and one O(8) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. In the fourth Co site, Co(4) is bonded to one O(1), one O(2), one O(6), one O(8), and one O(9) atom to form a mixture of distorted corner and edge-sharing CoO5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded to one Co(1), one Co(2), one Co(3), and one Co(4) atom to form a mixture of distorted corner and edge-sharing OCo4 trigonal pyramids. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(4) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Co(2) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(3), and one Co(4) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Co(1), one Co(2), and one Co(3) atom to form a mixture of distorted corner and edge-sharing OMgCo3 tetrahedra. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(3), and one Co(4) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Mg(1), one Co(1), one Co(2), and one Co(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCo4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.902
_cell_length_b   8.159
_cell_length_c   8.188
_cell_angle_alpha   89.705
_cell_angle_beta   90.004
_cell_angle_gamma   89.996
_symmetry_Int_Tables_number   1
_cell_volume   327.428
_cell_formula_units_Z   2
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  0.148  0.247  0.245  1.0
  Mg  Mg1  1  0.852  0.747  0.745  1.0
  Co  Co2  1  0.615  0.534  0.339  1.0
  Co  Co3  1  0.387  0.839  0.467  1.0
  Co  Co4  1  0.613  0.339  0.967  1.0
  Co  Co5  1  0.385  0.034  0.839  1.0
  Co  Co6  1  0.615  0.966  0.162  1.0
  Co  Co7  1  0.620  0.163  0.535  1.0
  Co  Co8  1  0.385  0.466  0.662  1.0
  Co  Co9  1  0.380  0.663  0.035  1.0
  O  O10  1  0.491  0.750  0.250  1.0
  O  O11  1  0.509  0.250  0.750  1.0
  O  O12  1  0.058  0.684  0.977  1.0
  O  O13  1  0.062  0.521  0.684  1.0
  O  O14  1  0.064  0.976  0.815  1.0
  O  O15  1  0.063  0.817  0.521  1.0
  O  O16  1  0.937  0.317  0.021  1.0
  O  O17  1  0.936  0.476  0.315  1.0
  O  O18  1  0.938  0.021  0.184  1.0
  O  O19  1  0.942  0.184  0.477  1.0
  O  O20  1  0.448  0.046  0.355  1.0
  O  O21  1  0.427  0.146  0.045  1.0
  O  O22  1  0.432  0.355  0.458  1.0
  O  O23  1  0.440  0.455  0.147  1.0
  O  O24  1  0.552  0.546  0.855  1.0
  O  O25  1  0.568  0.855  0.958  1.0
  O  O26  1  0.573  0.646  0.545  1.0
  O  O27  1  0.560  0.955  0.647  1.0
[/CIF]
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