The crystal structure described by LaSe2 crystallizes in the monoclinic P2_1/c space group. La(1) is bonded in a 9-coordinate geometry to four equivalent Se(1) and five equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to four equivalent La(1) and one Se(1) atom. In the second Se site, Se(2) is bonded to five equivalent La(1) atoms to form a mixture of distorted corner and edge-sharing SeLa5 trigonal bipyramids. is represented by the CIF card [CIF]
data_LaSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.281
_cell_length_b   8.549
_cell_length_c   8.624
_cell_angle_alpha   89.802
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   315.674
_cell_formula_units_Z   4
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
  La  La0  1  0.221  0.873  0.277  1.0
  La  La1  1  0.279  0.373  0.277  1.0
  La  La2  1  0.779  0.127  0.723  1.0
  La  La3  1  0.721  0.627  0.723  1.0
  Se  Se4  1  0.674  0.884  0.002  1.0
  Se  Se5  1  0.174  0.616  0.998  1.0
  Se  Se6  1  0.826  0.384  0.002  1.0
  Se  Se7  1  0.759  0.126  0.366  1.0
  Se  Se8  1  0.259  0.374  0.634  1.0
  Se  Se9  1  0.326  0.116  0.998  1.0
  Se  Se10  1  0.741  0.626  0.366  1.0
  Se  Se11  1  0.241  0.874  0.634  1.0
[/CIF]
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The crystal structure described by LaSe2 crystallizes in the monoclinic P2_1/c space group. La(1) is bonded in a 9-coordinate geometry to four equivalent Se(1) and five equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to four equivalent La(1) and one Se(1) atom. In the second Se site, Se(2) is bonded to five equivalent La(1) atoms to form a mixture of distorted corner and edge-sharing SeLa5 trigonal bipyramids. is represented by the CIF card [CIF]
data_LaSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.281
_cell_length_b   8.549
_cell_length_c   8.624
_cell_angle_alpha   89.802
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   315.674
_cell_formula_units_Z   4
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
  La  La0  1  0.221  0.873  0.277  1.0
  La  La1  1  0.279  0.373  0.277  1.0
  La  La2  1  0.779  0.127  0.723  1.0
  La  La3  1  0.721  0.627  0.723  1.0
  Se  Se4  1  0.674  0.884  0.002  1.0
  Se  Se5  1  0.174  0.616  0.998  1.0
  Se  Se6  1  0.826  0.384  0.002  1.0
  Se  Se7  1  0.759  0.126  0.366  1.0
  Se  Se8  1  0.259  0.374  0.634  1.0
  Se  Se9  1  0.326  0.116  0.998  1.0
  Se  Se10  1  0.741  0.626  0.366  1.0
  Se  Se11  1  0.241  0.874  0.634  1.0
[/CIF]
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