The crystal structure described by LiErSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. Li(1) is bonded to six Se(1,1,1,1) atoms to form LiSe6 octahedra that share corners with two equivalent Er(1)Se6 octahedra, corners with four equivalent Li(1)Se6 octahedra, edges with four equivalent Li(1)Se6 octahedra, and edges with eight equivalent Er(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Er(1) is bonded to six Se(1,1,1) atoms to form ErSe6 octahedra that share corners with two equivalent Li(1)Se6 octahedra, corners with four equivalent Er(1)Se6 octahedra, edges with four equivalent Er(1)Se6 octahedra, and edges with eight equivalent Li(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiErSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.974
_cell_length_b   6.974
_cell_length_c   6.974
_cell_angle_alpha   132.532
_cell_angle_beta   132.532
_cell_angle_gamma   69.391
_symmetry_Int_Tables_number   1
_cell_volume   180.688
_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  0.000  0.000  0.000  1.0
  Li  Li1  1  0.750  0.250  0.500  1.0
  Er  Er2  1  0.250  0.750  0.500  1.0
  Er  Er3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.746  0.746  0.000  1.0
  Se  Se5  1  0.496  0.996  0.500  1.0
  Se  Se6  1  0.254  0.254  0.000  1.0
  Se  Se7  1  0.004  0.504  0.500  1.0
[/CIF]
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The crystal structure described by LiErSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. Li(1) is bonded to six Se(1,1,1,1) atoms to form LiSe6 octahedra that share corners with two equivalent Er(1)Se6 octahedra, corners with four equivalent Li(1)Se6 octahedra, edges with four equivalent Li(1)Se6 octahedra, and edges with eight equivalent Er(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. Er(1) is bonded to six Se(1,1,1) atoms to form ErSe6 octahedra that share corners with two equivalent Li(1)Se6 octahedra, corners with four equivalent Er(1)Se6 octahedra, edges with four equivalent Er(1)Se6 octahedra, and edges with eight equivalent Li(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the fourth Se site, Se(1) is bonded to three equivalent Li(1) and three equivalent Er(1) atoms to form a mixture of corner and edge-sharing SeLi3Er3 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiErSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.974
_cell_length_b   6.974
_cell_length_c   6.974
_cell_angle_alpha   132.532
_cell_angle_beta   132.532
_cell_angle_gamma   69.391
_symmetry_Int_Tables_number   1
_cell_volume   180.688
_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  0.000  0.000  0.000  1.0
  Li  Li1  1  0.750  0.250  0.500  1.0
  Er  Er2  1  0.250  0.750  0.500  1.0
  Er  Er3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.746  0.746  0.000  1.0
  Se  Se5  1  0.496  0.996  0.500  1.0
  Se  Se6  1  0.254  0.254  0.000  1.0
  Se  Se7  1  0.004  0.504  0.500  1.0
[/CIF]
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