The material structure described by Zr4FeSe8 crystallizes in the monoclinic C2/m space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one Se(1), one Se(2), and four equivalent Se(3) atoms to form ZrSe6 octahedra that share corners with two equivalent Fe(1)Se6 octahedra, edges with two equivalent Zr(1)Se6 octahedra, edges with four equivalent Zr(2)Se6 octahedra, and  a faceface with one Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second Zr site, Zr(2) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form ZrSe6 octahedra that share corners with four equivalent Fe(1)Se6 octahedra, edges with two equivalent Zr(2)Se6 octahedra, and edges with four equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. Fe(1) is bonded to two equivalent Se(1) and four equivalent Se(3) atoms to form FeSe6 octahedra that share corners with four equivalent Zr(1)Se6 octahedra, corners with eight equivalent Zr(2)Se6 octahedra, and faces with two equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Zr(1), two equivalent Zr(2), and one Fe(1) atom. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Zr(1) and two equivalent Zr(2) atoms. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Zr(2), two equivalent Zr(1), and one Fe(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Zr4FeSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.314
_cell_length_b   7.314
_cell_length_c   9.039
_cell_angle_alpha   53.545
_cell_angle_beta   53.545
_cell_angle_gamma   61.925
_symmetry_Int_Tables_number   1
_cell_volume   307.579
_cell_formula_units_Z   1
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
  Zr  Zr0  1  0.246  0.246  0.005  1.0
  Zr  Zr1  1  0.754  0.754  0.995  1.0
  Zr  Zr2  1  0.757  0.243  0.500  1.0
  Zr  Zr3  1  0.243  0.757  0.500  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Se  Se5  1  0.287  0.287  0.667  1.0
  Se  Se6  1  0.787  0.787  0.667  1.0
  Se  Se7  1  0.284  0.786  0.166  1.0
  Se  Se8  1  0.786  0.284  0.166  1.0
  Se  Se9  1  0.214  0.716  0.834  1.0
  Se  Se10  1  0.716  0.214  0.834  1.0
  Se  Se11  1  0.213  0.213  0.333  1.0
  Se  Se12  1  0.713  0.713  0.333  1.0
[/CIF]
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The material structure described by Zr4FeSe8 crystallizes in the monoclinic C2/m space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded to one Se(1), one Se(2), and four equivalent Se(3) atoms to form ZrSe6 octahedra that share corners with two equivalent Fe(1)Se6 octahedra, edges with two equivalent Zr(1)Se6 octahedra, edges with four equivalent Zr(2)Se6 octahedra, and  a faceface with one Fe(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second Zr site, Zr(2) is bonded to two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form ZrSe6 octahedra that share corners with four equivalent Fe(1)Se6 octahedra, edges with two equivalent Zr(2)Se6 octahedra, and edges with four equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. Fe(1) is bonded to two equivalent Se(1) and four equivalent Se(3) atoms to form FeSe6 octahedra that share corners with four equivalent Zr(1)Se6 octahedra, corners with eight equivalent Zr(2)Se6 octahedra, and faces with two equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 48-49°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to one Zr(1), two equivalent Zr(2), and one Fe(1) atom. In the second Se site, Se(2) is bonded in a distorted T-shaped geometry to one Zr(1) and two equivalent Zr(2) atoms. In the third Se site, Se(3) is bonded in a rectangular see-saw-like geometry to one Zr(2), two equivalent Zr(1), and one Fe(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Zr4FeSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.314
_cell_length_b   7.314
_cell_length_c   9.039
_cell_angle_alpha   53.545
_cell_angle_beta   53.545
_cell_angle_gamma   61.925
_symmetry_Int_Tables_number   1
_cell_volume   307.579
_cell_formula_units_Z   1
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
  Zr  Zr0  1  0.246  0.246  0.005  1.0
  Zr  Zr1  1  0.754  0.754  0.995  1.0
  Zr  Zr2  1  0.757  0.243  0.500  1.0
  Zr  Zr3  1  0.243  0.757  0.500  1.0
  Fe  Fe4  1  0.000  0.000  0.000  1.0
  Se  Se5  1  0.287  0.287  0.667  1.0
  Se  Se6  1  0.787  0.787  0.667  1.0
  Se  Se7  1  0.284  0.786  0.166  1.0
  Se  Se8  1  0.786  0.284  0.166  1.0
  Se  Se9  1  0.214  0.716  0.834  1.0
  Se  Se10  1  0.716  0.214  0.834  1.0
  Se  Se11  1  0.213  0.213  0.333  1.0
  Se  Se12  1  0.713  0.713  0.333  1.0
[/CIF]
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