The material structure described by Nb2FeSe4 crystallizes in the orthorhombic Cmcm space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one Fe(2), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to one Fe(2), two equivalent Se(3), and four equivalent Se(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in an octahedral geometry to two equivalent Se(2) and four equivalent Se(1) atoms. In the second Fe site, Fe(2) is bonded in a 9-coordinate geometry to one Nb(3), two equivalent Nb(2), two equivalent Se(2), and four equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(3) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(2) atoms. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to one Nb(1), one Nb(2), one Nb(3), one Fe(1), and one Fe(2) atom. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Nb(1), two equivalent Nb(2), one Fe(1), and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2FeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.233
_cell_length_b   7.233
_cell_length_c   12.495
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.967
_symmetry_Int_Tables_number   1
_cell_volume   566.360
_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
  Nb  Nb0  1  1.000  0.000  0.250  1.0
  Nb  Nb1  1  0.000  1.000  0.750  1.0
  Nb  Nb2  1  0.474  0.949  0.250  1.0
  Nb  Nb3  1  0.474  0.526  0.250  1.0
  Nb  Nb4  1  0.051  0.526  0.250  1.0
  Nb  Nb5  1  0.526  0.051  0.750  1.0
  Nb  Nb6  1  0.526  0.474  0.750  1.0
  Nb  Nb7  1  0.949  0.474  0.750  1.0
  Fe  Fe8  1  0.000  0.000  0.000  1.0
  Fe  Fe9  1  0.000  0.000  0.500  1.0
  Fe  Fe10  1  0.666  0.334  0.250  1.0
  Fe  Fe11  1  0.334  0.666  0.750  1.0
  Se  Se12  1  0.832  0.663  0.122  1.0
  Se  Se13  1  0.831  0.169  0.122  1.0
  Se  Se14  1  0.337  0.168  0.122  1.0
  Se  Se15  1  0.168  0.337  0.878  1.0
  Se  Se16  1  0.169  0.831  0.878  1.0
  Se  Se17  1  0.663  0.832  0.878  1.0
  Se  Se18  1  0.168  0.337  0.622  1.0
  Se  Se19  1  0.169  0.831  0.622  1.0
  Se  Se20  1  0.663  0.832  0.622  1.0
  Se  Se21  1  0.832  0.663  0.378  1.0
  Se  Se22  1  0.831  0.169  0.378  1.0
  Se  Se23  1  0.337  0.168  0.378  1.0
  Se  Se24  1  0.667  0.333  0.600  1.0
  Se  Se25  1  0.333  0.667  0.400  1.0
  Se  Se26  1  0.333  0.667  0.100  1.0
  Se  Se27  1  0.667  0.333  0.900  1.0
[/CIF]
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The material structure described by Nb2FeSe4 crystallizes in the orthorhombic Cmcm space group. There are three inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to two equivalent Se(2) and four equivalent Se(1) atoms. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one Fe(2), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms. In the third Nb site, Nb(3) is bonded in a 7-coordinate geometry to one Fe(2), two equivalent Se(3), and four equivalent Se(1) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in an octahedral geometry to two equivalent Se(2) and four equivalent Se(1) atoms. In the second Fe site, Fe(2) is bonded in a 9-coordinate geometry to one Nb(3), two equivalent Nb(2), two equivalent Se(2), and four equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(3) is bonded in a 3-coordinate geometry to one Nb(3) and two equivalent Nb(2) atoms. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to one Nb(1), one Nb(2), one Nb(3), one Fe(1), and one Fe(2) atom. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Nb(1), two equivalent Nb(2), one Fe(1), and one Fe(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Nb2FeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.233
_cell_length_b   7.233
_cell_length_c   12.495
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.967
_symmetry_Int_Tables_number   1
_cell_volume   566.360
_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
  Nb  Nb0  1  1.000  0.000  0.250  1.0
  Nb  Nb1  1  0.000  1.000  0.750  1.0
  Nb  Nb2  1  0.474  0.949  0.250  1.0
  Nb  Nb3  1  0.474  0.526  0.250  1.0
  Nb  Nb4  1  0.051  0.526  0.250  1.0
  Nb  Nb5  1  0.526  0.051  0.750  1.0
  Nb  Nb6  1  0.526  0.474  0.750  1.0
  Nb  Nb7  1  0.949  0.474  0.750  1.0
  Fe  Fe8  1  0.000  0.000  0.000  1.0
  Fe  Fe9  1  0.000  0.000  0.500  1.0
  Fe  Fe10  1  0.666  0.334  0.250  1.0
  Fe  Fe11  1  0.334  0.666  0.750  1.0
  Se  Se12  1  0.832  0.663  0.122  1.0
  Se  Se13  1  0.831  0.169  0.122  1.0
  Se  Se14  1  0.337  0.168  0.122  1.0
  Se  Se15  1  0.168  0.337  0.878  1.0
  Se  Se16  1  0.169  0.831  0.878  1.0
  Se  Se17  1  0.663  0.832  0.878  1.0
  Se  Se18  1  0.168  0.337  0.622  1.0
  Se  Se19  1  0.169  0.831  0.622  1.0
  Se  Se20  1  0.663  0.832  0.622  1.0
  Se  Se21  1  0.832  0.663  0.378  1.0
  Se  Se22  1  0.831  0.169  0.378  1.0
  Se  Se23  1  0.337  0.168  0.378  1.0
  Se  Se24  1  0.667  0.333  0.600  1.0
  Se  Se25  1  0.333  0.667  0.400  1.0
  Se  Se26  1  0.333  0.667  0.100  1.0
  Se  Se27  1  0.667  0.333  0.900  1.0
[/CIF]
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