The material described by Li4SeO5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Se(1)O5 trigonal bipyramid, corners with three equivalent Li(1)O5 trigonal bipyramids, corners with four equivalent Li(2)O5 trigonal bipyramids,  an edgeedge with one Li(1)O5 trigonal bipyramid, edges with two equivalent Se(1)O5 trigonal bipyramids, and edges with three equivalent Li(2)O5 trigonal bipyramids. In the second Li site, Li(2) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Li(2)O5 trigonal bipyramid, corners with three equivalent Se(1)O5 trigonal bipyramids, corners with four equivalent Li(1)O5 trigonal bipyramids,  an edgeedge with one Se(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with three equivalent Li(1)O5 trigonal bipyramids. Se(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form SeO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with six equivalent Li(2)O5 trigonal bipyramids, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with four equivalent Li(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. is represented by the CIF card [CIF]
data_Li4SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.190
_cell_length_b   5.190
_cell_length_c   7.783
_cell_angle_alpha   83.130
_cell_angle_beta   83.130
_cell_angle_gamma   66.806
_symmetry_Int_Tables_number   1
_cell_volume   190.707
_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  0.362  0.034  0.354  1.0
  Li  Li1  1  0.966  0.638  0.146  1.0
  Li  Li2  1  0.566  0.223  0.943  1.0
  Li  Li3  1  0.777  0.434  0.557  1.0
  Li  Li4  1  0.434  0.777  0.057  1.0
  Li  Li5  1  0.223  0.566  0.443  1.0
  Li  Li6  1  0.638  0.966  0.646  1.0
  Li  Li7  1  0.034  0.362  0.854  1.0
  Se  Se8  1  0.828  0.172  0.250  1.0
  Se  Se9  1  0.172  0.828  0.750  1.0
  O  O10  1  0.007  0.350  0.340  1.0
  O  O11  1  0.650  0.993  0.160  1.0
  O  O12  1  0.870  0.130  0.750  1.0
  O  O13  1  0.130  0.870  0.250  1.0
  O  O14  1  0.412  0.767  0.572  1.0
  O  O15  1  0.233  0.588  0.928  1.0
  O  O16  1  0.588  0.233  0.428  1.0
  O  O17  1  0.767  0.412  0.072  1.0
  O  O18  1  0.350  0.007  0.840  1.0
  O  O19  1  0.993  0.650  0.660  1.0
[/CIF]
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The material described by Li4SeO5 crystallizes in the monoclinic C2/c space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Se(1)O5 trigonal bipyramid, corners with three equivalent Li(1)O5 trigonal bipyramids, corners with four equivalent Li(2)O5 trigonal bipyramids,  an edgeedge with one Li(1)O5 trigonal bipyramid, edges with two equivalent Se(1)O5 trigonal bipyramids, and edges with three equivalent Li(2)O5 trigonal bipyramids. In the second Li site, Li(2) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form LiO5 trigonal bipyramids that share  a cornercorner with one Li(2)O5 trigonal bipyramid, corners with three equivalent Se(1)O5 trigonal bipyramids, corners with four equivalent Li(1)O5 trigonal bipyramids,  an edgeedge with one Se(1)O5 trigonal bipyramid, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with three equivalent Li(1)O5 trigonal bipyramids. Se(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form SeO5 trigonal bipyramids that share corners with two equivalent Li(1)O5 trigonal bipyramids, corners with six equivalent Li(2)O5 trigonal bipyramids, edges with two equivalent Li(2)O5 trigonal bipyramids, and edges with four equivalent Li(1)O5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Li(1), two equivalent Li(2), and one Se(1) atom to form a mixture of corner and edge-sharing OLi4Se trigonal bipyramids. is represented by the CIF card [CIF]
data_Li4SeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.190
_cell_length_b   5.190
_cell_length_c   7.783
_cell_angle_alpha   83.130
_cell_angle_beta   83.130
_cell_angle_gamma   66.806
_symmetry_Int_Tables_number   1
_cell_volume   190.707
_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  0.362  0.034  0.354  1.0
  Li  Li1  1  0.966  0.638  0.146  1.0
  Li  Li2  1  0.566  0.223  0.943  1.0
  Li  Li3  1  0.777  0.434  0.557  1.0
  Li  Li4  1  0.434  0.777  0.057  1.0
  Li  Li5  1  0.223  0.566  0.443  1.0
  Li  Li6  1  0.638  0.966  0.646  1.0
  Li  Li7  1  0.034  0.362  0.854  1.0
  Se  Se8  1  0.828  0.172  0.250  1.0
  Se  Se9  1  0.172  0.828  0.750  1.0
  O  O10  1  0.007  0.350  0.340  1.0
  O  O11  1  0.650  0.993  0.160  1.0
  O  O12  1  0.870  0.130  0.750  1.0
  O  O13  1  0.130  0.870  0.250  1.0
  O  O14  1  0.412  0.767  0.572  1.0
  O  O15  1  0.233  0.588  0.928  1.0
  O  O16  1  0.588  0.233  0.428  1.0
  O  O17  1  0.767  0.412  0.072  1.0
  O  O18  1  0.350  0.007  0.840  1.0
  O  O19  1  0.993  0.650  0.660  1.0
[/CIF]
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