The crystal structure described by Li2H2SeO5 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form LiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with four equivalent Se(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form LiO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with three equivalent Se(1)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. Se(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SeO4 tetrahedra that share corners with three equivalent Li(2)O4 tetrahedra and corners with four equivalent Li(1)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Li(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Li(2), one H(1), and one H(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2H2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.030
_cell_length_b   5.950
_cell_length_c   8.452
_cell_angle_alpha   75.024
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   244.390
_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
  Li  Li0  1  0.991  0.312  0.996  1.0
  Li  Li1  1  0.472  0.863  0.579  1.0
  Li  Li2  1  0.972  0.137  0.421  1.0
  Li  Li3  1  0.491  0.688  0.004  1.0
  H  H4  1  0.866  0.313  0.644  1.0
  H  H5  1  0.543  0.512  0.485  1.0
  H  H6  1  0.043  0.488  0.515  1.0
  H  H7  1  0.366  0.687  0.356  1.0
  Se  Se8  1  0.483  0.121  0.198  1.0
  Se  Se9  1  0.983  0.879  0.802  1.0
  O  O10  1  0.888  0.128  0.842  1.0
  O  O11  1  0.381  0.611  0.475  1.0
  O  O12  1  0.867  0.652  0.947  1.0
  O  O13  1  0.815  0.141  0.207  1.0
  O  O14  1  0.363  0.126  0.382  1.0
  O  O15  1  0.863  0.874  0.618  1.0
  O  O16  1  0.315  0.859  0.793  1.0
  O  O17  1  0.367  0.348  0.053  1.0
  O  O18  1  0.881  0.389  0.525  1.0
  O  O19  1  0.388  0.872  0.158  1.0
[/CIF]
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The crystal structure described by Li2H2SeO5 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(4), and two equivalent O(3) atoms to form LiO4 tetrahedra that share  a cornercorner with one Li(2)O4 tetrahedra, corners with two equivalent Li(1)O4 tetrahedra, and corners with four equivalent Se(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(2), one O(4), and two equivalent O(5) atoms to form LiO4 tetrahedra that share  a cornercorner with one Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with three equivalent Se(1)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. Se(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form SeO4 tetrahedra that share corners with three equivalent Li(2)O4 tetrahedra and corners with four equivalent Li(1)O4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Li(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Li(2), one H(1), and one H(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Se(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2H2SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.030
_cell_length_b   5.950
_cell_length_c   8.452
_cell_angle_alpha   75.024
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   244.390
_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
  Li  Li0  1  0.991  0.312  0.996  1.0
  Li  Li1  1  0.472  0.863  0.579  1.0
  Li  Li2  1  0.972  0.137  0.421  1.0
  Li  Li3  1  0.491  0.688  0.004  1.0
  H  H4  1  0.866  0.313  0.644  1.0
  H  H5  1  0.543  0.512  0.485  1.0
  H  H6  1  0.043  0.488  0.515  1.0
  H  H7  1  0.366  0.687  0.356  1.0
  Se  Se8  1  0.483  0.121  0.198  1.0
  Se  Se9  1  0.983  0.879  0.802  1.0
  O  O10  1  0.888  0.128  0.842  1.0
  O  O11  1  0.381  0.611  0.475  1.0
  O  O12  1  0.867  0.652  0.947  1.0
  O  O13  1  0.815  0.141  0.207  1.0
  O  O14  1  0.363  0.126  0.382  1.0
  O  O15  1  0.863  0.874  0.618  1.0
  O  O16  1  0.315  0.859  0.793  1.0
  O  O17  1  0.367  0.348  0.053  1.0
  O  O18  1  0.881  0.389  0.525  1.0
  O  O19  1  0.388  0.872  0.158  1.0
[/CIF]
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