The material described by Zr2NiSe4 crystallizes in the monoclinic C2/m space group. Zr(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form ZrSe6 octahedra that share corners with six equivalent Ni(1)Se6 octahedra, edges with six equivalent Zr(1)Se6 octahedra, and  a faceface with one Ni(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 49°. Ni(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form distorted NiSe6 octahedra that share corners with twelve equivalent Zr(1)Se6 octahedra, edges with two equivalent Ni(1)Se6 octahedra, and faces with two equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to three equivalent Zr(1) and one Ni(1) atom. In the second Se site, Se(2) is bonded to three equivalent Zr(1) and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing SeZr3Ni2 square pyramids. is represented by the CIF card [CIF]
data_Zr2NiSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.746
_cell_length_b   7.100
_cell_length_c   6.449
_cell_angle_alpha   63.383
_cell_angle_beta   90.019
_cell_angle_gamma   105.313
_symmetry_Int_Tables_number   1
_cell_volume   146.504
_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  0.502  0.005  0.500  1.0
  Zr  Zr1  1  0.998  0.995  0.000  1.0
  Ni  Ni2  1  0.250  0.500  0.750  1.0
  Se  Se3  1  0.137  0.274  0.534  1.0
  Se  Se4  1  0.637  0.272  0.031  1.0
  Se  Se5  1  0.863  0.728  0.469  1.0
  Se  Se6  1  0.363  0.726  0.966  1.0
[/CIF]
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The material described by Zr2NiSe4 crystallizes in the monoclinic C2/m space group. Zr(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form ZrSe6 octahedra that share corners with six equivalent Ni(1)Se6 octahedra, edges with six equivalent Zr(1)Se6 octahedra, and  a faceface with one Ni(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 49°. Ni(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form distorted NiSe6 octahedra that share corners with twelve equivalent Zr(1)Se6 octahedra, edges with two equivalent Ni(1)Se6 octahedra, and faces with two equivalent Zr(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to three equivalent Zr(1) and one Ni(1) atom. In the second Se site, Se(2) is bonded to three equivalent Zr(1) and two equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing SeZr3Ni2 square pyramids. is represented by the CIF card [CIF]
data_Zr2NiSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.746
_cell_length_b   7.100
_cell_length_c   6.449
_cell_angle_alpha   63.383
_cell_angle_beta   90.019
_cell_angle_gamma   105.313
_symmetry_Int_Tables_number   1
_cell_volume   146.504
_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  0.502  0.005  0.500  1.0
  Zr  Zr1  1  0.998  0.995  0.000  1.0
  Ni  Ni2  1  0.250  0.500  0.750  1.0
  Se  Se3  1  0.137  0.274  0.534  1.0
  Se  Se4  1  0.637  0.272  0.031  1.0
  Se  Se5  1  0.863  0.728  0.469  1.0
  Se  Se6  1  0.363  0.726  0.966  1.0
[/CIF]
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