The crystal structure described by MgH2 is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a 7-coordinate geometry to three equivalent H(1) and four equivalent H(2) atoms. There are two inequivalent H sites. In the first H site, H(2) is bonded to four equivalent Mg(1) atoms to form a mixture of corner and edge-sharing HMg4 tetrahedra. In the second H site, H(1) is bonded in a 3-coordinate geometry to three equivalent Mg(1) atoms. is represented by the CIF card [CIF]
data_MgH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.113
_cell_length_b   5.301
_cell_length_c   5.997
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   98.965
_cell_formula_units_Z   4
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  0.250  0.748  0.603  1.0
  Mg  Mg1  1  0.750  0.252  0.397  1.0
  Mg  Mg2  1  0.250  0.248  0.897  1.0
  Mg  Mg3  1  0.750  0.752  0.103  1.0
  H  H4  1  0.250  0.477  0.167  1.0
  H  H5  1  0.750  0.523  0.833  1.0
  H  H6  1  0.250  0.977  0.333  1.0
  H  H7  1  0.750  0.023  0.667  1.0
  H  H8  1  0.750  0.639  0.425  1.0
  H  H9  1  0.250  0.361  0.575  1.0
  H  H10  1  0.750  0.139  0.075  1.0
  H  H11  1  0.250  0.861  0.925  1.0
[/CIF]
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The crystal structure described by MgH2 is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. Mg(1) is bonded in a 7-coordinate geometry to three equivalent H(1) and four equivalent H(2) atoms. There are two inequivalent H sites. In the first H site, H(2) is bonded to four equivalent Mg(1) atoms to form a mixture of corner and edge-sharing HMg4 tetrahedra. In the second H site, H(1) is bonded in a 3-coordinate geometry to three equivalent Mg(1) atoms. is represented by the CIF card [CIF]
data_MgH2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.113
_cell_length_b   5.301
_cell_length_c   5.997
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   98.965
_cell_formula_units_Z   4
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  0.250  0.748  0.603  1.0
  Mg  Mg1  1  0.750  0.252  0.397  1.0
  Mg  Mg2  1  0.250  0.248  0.897  1.0
  Mg  Mg3  1  0.750  0.752  0.103  1.0
  H  H4  1  0.250  0.477  0.167  1.0
  H  H5  1  0.750  0.523  0.833  1.0
  H  H6  1  0.250  0.977  0.333  1.0
  H  H7  1  0.750  0.023  0.667  1.0
  H  H8  1  0.750  0.639  0.425  1.0
  H  H9  1  0.250  0.361  0.575  1.0
  H  H10  1  0.750  0.139  0.075  1.0
  H  H11  1  0.250  0.861  0.925  1.0
[/CIF]
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