The material structure described by MgH2(SeO4)2 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. H(1) is bonded in a distorted linear geometry to one O(1) and one O(4) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-47°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one H(1) and one Se(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(1), and one Se(1) atom. is represented by the CIF file [CIF]
data_MgH2(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.691
_cell_length_b   5.212
_cell_length_c   8.573
_cell_angle_alpha   61.530
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   341.360
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.000  0.500  1.0
  H  H2  1  0.987  0.442  0.347  1.0
  H  H3  1  0.487  0.558  0.153  1.0
  H  H4  1  0.013  0.558  0.653  1.0
  H  H5  1  0.513  0.442  0.847  1.0
  Se  Se6  1  0.818  0.664  0.785  1.0
  Se  Se7  1  0.318  0.336  0.715  1.0
  Se  Se8  1  0.682  0.664  0.285  1.0
  Se  Se9  1  0.182  0.336  0.215  1.0
  O  O10  1  0.081  0.313  0.398  1.0
  O  O11  1  0.581  0.687  0.102  1.0
  O  O12  1  0.351  0.658  0.542  1.0
  O  O13  1  0.851  0.342  0.958  1.0
  O  O14  1  0.649  0.342  0.458  1.0
  O  O15  1  0.149  0.658  0.042  1.0
  O  O16  1  0.368  0.058  0.685  1.0
  O  O17  1  0.868  0.942  0.815  1.0
  O  O18  1  0.632  0.942  0.315  1.0
  O  O19  1  0.132  0.058  0.185  1.0
  O  O20  1  0.135  0.305  0.780  1.0
  O  O21  1  0.635  0.695  0.720  1.0
  O  O22  1  0.865  0.695  0.220  1.0
  O  O23  1  0.365  0.305  0.280  1.0
  O  O24  1  0.419  0.313  0.898  1.0
  O  O25  1  0.919  0.687  0.602  1.0
[/CIF]
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The material structure described by MgH2(SeO4)2 crystallizes in the monoclinic P2_1/c space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra. H(1) is bonded in a distorted linear geometry to one O(1) and one O(4) atom. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-47°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a water-like geometry to one H(1) and one Se(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one Se(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(1), and one Se(1) atom. is represented by the CIF file [CIF]
data_MgH2(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.691
_cell_length_b   5.212
_cell_length_c   8.573
_cell_angle_alpha   61.530
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   341.360
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.500  0.000  0.500  1.0
  H  H2  1  0.987  0.442  0.347  1.0
  H  H3  1  0.487  0.558  0.153  1.0
  H  H4  1  0.013  0.558  0.653  1.0
  H  H5  1  0.513  0.442  0.847  1.0
  Se  Se6  1  0.818  0.664  0.785  1.0
  Se  Se7  1  0.318  0.336  0.715  1.0
  Se  Se8  1  0.682  0.664  0.285  1.0
  Se  Se9  1  0.182  0.336  0.215  1.0
  O  O10  1  0.081  0.313  0.398  1.0
  O  O11  1  0.581  0.687  0.102  1.0
  O  O12  1  0.351  0.658  0.542  1.0
  O  O13  1  0.851  0.342  0.958  1.0
  O  O14  1  0.649  0.342  0.458  1.0
  O  O15  1  0.149  0.658  0.042  1.0
  O  O16  1  0.368  0.058  0.685  1.0
  O  O17  1  0.868  0.942  0.815  1.0
  O  O18  1  0.632  0.942  0.315  1.0
  O  O19  1  0.132  0.058  0.185  1.0
  O  O20  1  0.135  0.305  0.780  1.0
  O  O21  1  0.635  0.695  0.720  1.0
  O  O22  1  0.865  0.695  0.220  1.0
  O  O23  1  0.365  0.305  0.280  1.0
  O  O24  1  0.419  0.313  0.898  1.0
  O  O25  1  0.919  0.687  0.602  1.0
[/CIF]
.