The material described by PmSe2 crystallizes in the monoclinic P2_1/c space group. Pm(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 Pm(1) and one Se(1) atom. In the second Se site, Se(2) is bonded to five equivalent Pm(1) atoms to form a mixture of distorted corner and edge-sharing SePm5 trigonal bipyramids. is represented by the CIF card [CIF]
data_PmSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.167
_cell_length_b   8.382
_cell_length_c   8.463
_cell_angle_alpha   89.804
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   295.608
_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
  Pm  Pm0  1  0.279  0.373  0.275  1.0
  Pm  Pm1  1  0.721  0.627  0.725  1.0
  Pm  Pm2  1  0.221  0.873  0.275  1.0
  Pm  Pm3  1  0.779  0.127  0.725  1.0
  Se  Se4  1  0.183  0.618  0.998  1.0
  Se  Se5  1  0.757  0.125  0.369  1.0
  Se  Se6  1  0.243  0.875  0.631  1.0
  Se  Se7  1  0.257  0.375  0.631  1.0
  Se  Se8  1  0.683  0.882  0.002  1.0
  Se  Se9  1  0.743  0.625  0.369  1.0
  Se  Se10  1  0.817  0.382  0.002  1.0
  Se  Se11  1  0.317  0.118  0.998  1.0
[/CIF]
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The material described by PmSe2 crystallizes in the monoclinic P2_1/c space group. Pm(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 Pm(1) and one Se(1) atom. In the second Se site, Se(2) is bonded to five equivalent Pm(1) atoms to form a mixture of distorted corner and edge-sharing SePm5 trigonal bipyramids. is represented by the CIF card [CIF]
data_PmSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.167
_cell_length_b   8.382
_cell_length_c   8.463
_cell_angle_alpha   89.804
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   295.608
_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
  Pm  Pm0  1  0.279  0.373  0.275  1.0
  Pm  Pm1  1  0.721  0.627  0.725  1.0
  Pm  Pm2  1  0.221  0.873  0.275  1.0
  Pm  Pm3  1  0.779  0.127  0.725  1.0
  Se  Se4  1  0.183  0.618  0.998  1.0
  Se  Se5  1  0.757  0.125  0.369  1.0
  Se  Se6  1  0.243  0.875  0.631  1.0
  Se  Se7  1  0.257  0.375  0.631  1.0
  Se  Se8  1  0.683  0.882  0.002  1.0
  Se  Se9  1  0.743  0.625  0.369  1.0
  Se  Se10  1  0.817  0.382  0.002  1.0
  Se  Se11  1  0.317  0.118  0.998  1.0
[/CIF]
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