The material structure described by FePSe crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to three equivalent P(1) and three equivalent Se(1) atoms to form FeP3Se3 octahedra that share corners with eight equivalent Fe(1)P3Se3 octahedra, corners with three equivalent P(1)Fe3Se tetrahedra, corners with three equivalent Se(1)Fe3P tetrahedra, and edges with two equivalent Fe(1)P3Se3 octahedra. The corner-sharing octahedral tilt angles range from 54-59°. P(1) is bonded to three equivalent Fe(1) and one Se(1) atom to form distorted PFe3Se tetrahedra that share corners with three equivalent Fe(1)P3Se3 octahedra, corners with four equivalent P(1)Fe3Se tetrahedra, corners with nine equivalent Se(1)Fe3P tetrahedra, and  an edgeedge with one P(1)Fe3Se tetrahedra. The corner-sharing octahedral tilt angles range from 66-73°. Se(1) is bonded to three equivalent Fe(1) and one P(1) atom to form distorted SeFe3P tetrahedra that share corners with three equivalent Fe(1)P3Se3 octahedra, corners with four equivalent Se(1)Fe3P tetrahedra, corners with nine equivalent P(1)Fe3Se tetrahedra, and  an edgeedge with one Se(1)Fe3P tetrahedra. The corner-sharing octahedral tilt angles range from 74-81°. is represented by the CIF file [CIF]
data_FePSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.714
_cell_length_b   5.737
_cell_length_c   5.806
_cell_angle_alpha   67.313
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   175.604
_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
  Fe  Fe0  1  0.991  0.736  0.288  1.0
  Fe  Fe1  1  0.491  0.264  0.212  1.0
  Fe  Fe2  1  0.009  0.264  0.712  1.0
  Fe  Fe3  1  0.509  0.736  0.788  1.0
  P  P4  1  0.635  0.859  0.382  1.0
  P  P5  1  0.135  0.141  0.118  1.0
  P  P6  1  0.365  0.141  0.618  1.0
  P  P7  1  0.865  0.859  0.882  1.0
  Se  Se8  1  0.371  0.662  0.185  1.0
  Se  Se9  1  0.871  0.338  0.315  1.0
  Se  Se10  1  0.629  0.338  0.815  1.0
  Se  Se11  1  0.129  0.662  0.685  1.0
[/CIF]
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The material structure described by FePSe crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to three equivalent P(1) and three equivalent Se(1) atoms to form FeP3Se3 octahedra that share corners with eight equivalent Fe(1)P3Se3 octahedra, corners with three equivalent P(1)Fe3Se tetrahedra, corners with three equivalent Se(1)Fe3P tetrahedra, and edges with two equivalent Fe(1)P3Se3 octahedra. The corner-sharing octahedral tilt angles range from 54-59°. P(1) is bonded to three equivalent Fe(1) and one Se(1) atom to form distorted PFe3Se tetrahedra that share corners with three equivalent Fe(1)P3Se3 octahedra, corners with four equivalent P(1)Fe3Se tetrahedra, corners with nine equivalent Se(1)Fe3P tetrahedra, and  an edgeedge with one P(1)Fe3Se tetrahedra. The corner-sharing octahedral tilt angles range from 66-73°. Se(1) is bonded to three equivalent Fe(1) and one P(1) atom to form distorted SeFe3P tetrahedra that share corners with three equivalent Fe(1)P3Se3 octahedra, corners with four equivalent Se(1)Fe3P tetrahedra, corners with nine equivalent P(1)Fe3Se tetrahedra, and  an edgeedge with one Se(1)Fe3P tetrahedra. The corner-sharing octahedral tilt angles range from 74-81°. is represented by the CIF file [CIF]
data_FePSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.714
_cell_length_b   5.737
_cell_length_c   5.806
_cell_angle_alpha   67.313
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   175.604
_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
  Fe  Fe0  1  0.991  0.736  0.288  1.0
  Fe  Fe1  1  0.491  0.264  0.212  1.0
  Fe  Fe2  1  0.009  0.264  0.712  1.0
  Fe  Fe3  1  0.509  0.736  0.788  1.0
  P  P4  1  0.635  0.859  0.382  1.0
  P  P5  1  0.135  0.141  0.118  1.0
  P  P6  1  0.365  0.141  0.618  1.0
  P  P7  1  0.865  0.859  0.882  1.0
  Se  Se8  1  0.371  0.662  0.185  1.0
  Se  Se9  1  0.871  0.338  0.315  1.0
  Se  Se10  1  0.629  0.338  0.815  1.0
  Se  Se11  1  0.129  0.662  0.685  1.0
[/CIF]
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