The crystal structure described by MgO crystallizes in the hexagonal P6/mcc space group. Mg(1) is bonded to five equivalent O(1) atoms to form a mixture of corner and edge-sharing MgO5 trigonal bipyramids. O(1) is bonded to five equivalent Mg(1) atoms to form a mixture of corner and edge-sharing OMg5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.668
_cell_length_b   9.668
_cell_length_c   4.188
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.050
_cell_formula_units_Z   12
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  0.122  0.668  0.000  1.0
  Mg  Mg1  1  0.332  0.454  0.000  1.0
  Mg  Mg2  1  0.546  0.878  0.000  1.0
  Mg  Mg3  1  0.668  0.122  0.500  1.0
  Mg  Mg4  1  0.454  0.332  0.500  1.0
  Mg  Mg5  1  0.878  0.546  0.500  1.0
  Mg  Mg6  1  0.878  0.332  0.000  1.0
  Mg  Mg7  1  0.668  0.546  0.000  1.0
  Mg  Mg8  1  0.454  0.122  0.000  1.0
  Mg  Mg9  1  0.332  0.878  0.500  1.0
  Mg  Mg10  1  0.546  0.668  0.500  1.0
  Mg  Mg11  1  0.122  0.454  0.500  1.0
  O  O12  1  0.122  0.671  0.500  1.0
  O  O13  1  0.329  0.451  0.500  1.0
  O  O14  1  0.549  0.878  0.500  1.0
  O  O15  1  0.671  0.122  0.000  1.0
  O  O16  1  0.451  0.329  0.000  1.0
  O  O17  1  0.878  0.549  0.000  1.0
  O  O18  1  0.878  0.329  0.500  1.0
  O  O19  1  0.671  0.549  0.500  1.0
  O  O20  1  0.451  0.122  0.500  1.0
  O  O21  1  0.329  0.878  0.000  1.0
  O  O22  1  0.549  0.671  0.000  1.0
  O  O23  1  0.122  0.451  0.000  1.0
[/CIF]
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The crystal structure described by MgO crystallizes in the hexagonal P6/mcc space group. Mg(1) is bonded to five equivalent O(1) atoms to form a mixture of corner and edge-sharing MgO5 trigonal bipyramids. O(1) is bonded to five equivalent Mg(1) atoms to form a mixture of corner and edge-sharing OMg5 trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.668
_cell_length_b   9.668
_cell_length_c   4.188
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   339.050
_cell_formula_units_Z   12
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  0.122  0.668  0.000  1.0
  Mg  Mg1  1  0.332  0.454  0.000  1.0
  Mg  Mg2  1  0.546  0.878  0.000  1.0
  Mg  Mg3  1  0.668  0.122  0.500  1.0
  Mg  Mg4  1  0.454  0.332  0.500  1.0
  Mg  Mg5  1  0.878  0.546  0.500  1.0
  Mg  Mg6  1  0.878  0.332  0.000  1.0
  Mg  Mg7  1  0.668  0.546  0.000  1.0
  Mg  Mg8  1  0.454  0.122  0.000  1.0
  Mg  Mg9  1  0.332  0.878  0.500  1.0
  Mg  Mg10  1  0.546  0.668  0.500  1.0
  Mg  Mg11  1  0.122  0.454  0.500  1.0
  O  O12  1  0.122  0.671  0.500  1.0
  O  O13  1  0.329  0.451  0.500  1.0
  O  O14  1  0.549  0.878  0.500  1.0
  O  O15  1  0.671  0.122  0.000  1.0
  O  O16  1  0.451  0.329  0.000  1.0
  O  O17  1  0.878  0.549  0.000  1.0
  O  O18  1  0.878  0.329  0.500  1.0
  O  O19  1  0.671  0.549  0.500  1.0
  O  O20  1  0.451  0.122  0.500  1.0
  O  O21  1  0.329  0.878  0.000  1.0
  O  O22  1  0.549  0.671  0.000  1.0
  O  O23  1  0.122  0.451  0.000  1.0
[/CIF]
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