The material described by Li2SeO4 crystallizes in the trigonal R-3 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)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(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with four equivalent Se(1)O4 tetrahedra. 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 four equivalent Li(1)O4 tetrahedra and corners with four equivalent Li(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Se(1) atom. In the second O site, O(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Se(1) atom. In the third O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. In the fourth O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Li2SeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.619
_cell_length_b   8.619
_cell_length_c   8.619
_cell_angle_alpha   107.804
_cell_angle_beta   107.804
_cell_angle_gamma   107.804
_symmetry_Int_Tables_number   1
_cell_volume   521.068
_cell_formula_units_Z   6
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  0.295  0.065  0.892  1.0
  Li  Li1  1  0.065  0.892  0.295  1.0
  Li  Li2  1  0.892  0.295  0.065  1.0
  Li  Li3  1  0.705  0.935  0.108  1.0
  Li  Li4  1  0.935  0.108  0.705  1.0
  Li  Li5  1  0.108  0.705  0.935  1.0
  Li  Li6  1  0.622  0.400  0.222  1.0
  Li  Li7  1  0.400  0.222  0.622  1.0
  Li  Li8  1  0.222  0.622  0.400  1.0
  Li  Li9  1  0.378  0.600  0.778  1.0
  Li  Li10  1  0.600  0.778  0.378  1.0
  Li  Li11  1  0.778  0.378  0.600  1.0
  Se  Se12  1  0.962  0.736  0.551  1.0
  Se  Se13  1  0.449  0.038  0.264  1.0
  Se  Se14  1  0.264  0.449  0.038  1.0
  Se  Se15  1  0.038  0.264  0.449  1.0
  Se  Se16  1  0.551  0.962  0.736  1.0
  Se  Se17  1  0.736  0.551  0.962  1.0
  O  O18  1  0.525  0.472  0.811  1.0
  O  O19  1  0.528  0.189  0.475  1.0
  O  O20  1  0.475  0.528  0.189  1.0
  O  O21  1  0.189  0.475  0.528  1.0
  O  O22  1  0.472  0.811  0.525  1.0
  O  O23  1  0.147  0.138  0.466  1.0
  O  O24  1  0.853  0.862  0.534  1.0
  O  O25  1  0.862  0.534  0.853  1.0
  O  O26  1  0.534  0.853  0.862  1.0
  O  O27  1  0.924  0.252  0.570  1.0
  O  O28  1  0.138  0.466  0.147  1.0
  O  O29  1  0.466  0.147  0.138  1.0
  O  O30  1  0.076  0.748  0.430  1.0
  O  O31  1  0.748  0.430  0.076  1.0
  O  O32  1  0.430  0.076  0.748  1.0
  O  O33  1  0.234  0.897  0.185  1.0
  O  O34  1  0.252  0.570  0.924  1.0
  O  O35  1  0.570  0.924  0.252  1.0
  O  O36  1  0.103  0.815  0.766  1.0
  O  O37  1  0.815  0.766  0.103  1.0
  O  O38  1  0.766  0.103  0.815  1.0
  O  O39  1  0.897  0.185  0.234  1.0
  O  O40  1  0.185  0.234  0.897  1.0
  O  O41  1  0.811  0.525  0.472  1.0
[/CIF]
.
The material described by Li2SeO4 crystallizes in the trigonal R-3 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(3), and two equivalent O(4) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)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(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Li(2)O4 tetrahedra, and corners with four equivalent Se(1)O4 tetrahedra. 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 four equivalent Li(1)O4 tetrahedra and corners with four equivalent Li(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a trigonal planar geometry to two equivalent Li(1) and one Se(1) atom. In the second O site, O(1) is bonded in a trigonal planar geometry to two equivalent Li(2) and one Se(1) atom. In the third O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. In the fourth O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Li2SeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.619
_cell_length_b   8.619
_cell_length_c   8.619
_cell_angle_alpha   107.804
_cell_angle_beta   107.804
_cell_angle_gamma   107.804
_symmetry_Int_Tables_number   1
_cell_volume   521.068
_cell_formula_units_Z   6
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  0.295  0.065  0.892  1.0
  Li  Li1  1  0.065  0.892  0.295  1.0
  Li  Li2  1  0.892  0.295  0.065  1.0
  Li  Li3  1  0.705  0.935  0.108  1.0
  Li  Li4  1  0.935  0.108  0.705  1.0
  Li  Li5  1  0.108  0.705  0.935  1.0
  Li  Li6  1  0.622  0.400  0.222  1.0
  Li  Li7  1  0.400  0.222  0.622  1.0
  Li  Li8  1  0.222  0.622  0.400  1.0
  Li  Li9  1  0.378  0.600  0.778  1.0
  Li  Li10  1  0.600  0.778  0.378  1.0
  Li  Li11  1  0.778  0.378  0.600  1.0
  Se  Se12  1  0.962  0.736  0.551  1.0
  Se  Se13  1  0.449  0.038  0.264  1.0
  Se  Se14  1  0.264  0.449  0.038  1.0
  Se  Se15  1  0.038  0.264  0.449  1.0
  Se  Se16  1  0.551  0.962  0.736  1.0
  Se  Se17  1  0.736  0.551  0.962  1.0
  O  O18  1  0.525  0.472  0.811  1.0
  O  O19  1  0.528  0.189  0.475  1.0
  O  O20  1  0.475  0.528  0.189  1.0
  O  O21  1  0.189  0.475  0.528  1.0
  O  O22  1  0.472  0.811  0.525  1.0
  O  O23  1  0.147  0.138  0.466  1.0
  O  O24  1  0.853  0.862  0.534  1.0
  O  O25  1  0.862  0.534  0.853  1.0
  O  O26  1  0.534  0.853  0.862  1.0
  O  O27  1  0.924  0.252  0.570  1.0
  O  O28  1  0.138  0.466  0.147  1.0
  O  O29  1  0.466  0.147  0.138  1.0
  O  O30  1  0.076  0.748  0.430  1.0
  O  O31  1  0.748  0.430  0.076  1.0
  O  O32  1  0.430  0.076  0.748  1.0
  O  O33  1  0.234  0.897  0.185  1.0
  O  O34  1  0.252  0.570  0.924  1.0
  O  O35  1  0.570  0.924  0.252  1.0
  O  O36  1  0.103  0.815  0.766  1.0
  O  O37  1  0.815  0.766  0.103  1.0
  O  O38  1  0.766  0.103  0.815  1.0
  O  O39  1  0.897  0.185  0.234  1.0
  O  O40  1  0.185  0.234  0.897  1.0
  O  O41  1  0.811  0.525  0.472  1.0
[/CIF]
.