The compound described by K2Ni3Se4 crystallizes in the orthorhombic Fddd space group. K(1) is bonded in a 14-coordinate geometry to two equivalent Ni(1), four equivalent Ni(2), and eight equivalent Se(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to four equivalent K(1) and four equivalent Se(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent K(1) and four equivalent Se(1) atoms. Se(1) is bonded in a 7-coordinate geometry to four equivalent K(1), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_K2Ni3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.345
_cell_length_b   13.676
_cell_length_c   6.100
_cell_angle_alpha   83.646
_cell_angle_beta   71.354
_cell_angle_gamma   25.000
_symmetry_Int_Tables_number   1
_cell_volume   428.588
_cell_formula_units_Z   2
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
  K  K0  1  0.924  0.924  0.076  1.0
  K  K1  1  0.076  0.076  0.924  1.0
  K  K2  1  0.326  0.326  0.174  1.0
  K  K3  1  0.174  0.174  0.326  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.750  0.750  0.750  1.0
  Ni  Ni6  1  0.250  0.250  0.750  1.0
  Ni  Ni7  1  0.750  0.750  0.250  1.0
  Ni  Ni8  1  1.000  1.000  0.500  1.0
  Ni  Ni9  1  0.500  0.500  1.000  1.0
  Se  Se10  1  0.389  0.727  0.277  1.0
  Se  Se11  1  0.277  0.606  0.389  1.0
  Se  Se12  1  0.727  0.389  0.606  1.0
  Se  Se13  1  0.606  0.277  0.727  1.0
  Se  Se14  1  0.861  0.523  0.973  1.0
  Se  Se15  1  0.973  0.644  0.861  1.0
  Se  Se16  1  0.523  0.861  0.644  1.0
  Se  Se17  1  0.644  0.973  0.523  1.0
[/CIF]
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The compound described by K2Ni3Se4 crystallizes in the orthorhombic Fddd space group. K(1) is bonded in a 14-coordinate geometry to two equivalent Ni(1), four equivalent Ni(2), and eight equivalent Se(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to four equivalent K(1) and four equivalent Se(1) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to four equivalent K(1) and four equivalent Se(1) atoms. Se(1) is bonded in a 7-coordinate geometry to four equivalent K(1), one Ni(1), and two equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_K2Ni3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.345
_cell_length_b   13.676
_cell_length_c   6.100
_cell_angle_alpha   83.646
_cell_angle_beta   71.354
_cell_angle_gamma   25.000
_symmetry_Int_Tables_number   1
_cell_volume   428.588
_cell_formula_units_Z   2
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
  K  K0  1  0.924  0.924  0.076  1.0
  K  K1  1  0.076  0.076  0.924  1.0
  K  K2  1  0.326  0.326  0.174  1.0
  K  K3  1  0.174  0.174  0.326  1.0
  Ni  Ni4  1  0.500  0.500  0.500  1.0
  Ni  Ni5  1  0.750  0.750  0.750  1.0
  Ni  Ni6  1  0.250  0.250  0.750  1.0
  Ni  Ni7  1  0.750  0.750  0.250  1.0
  Ni  Ni8  1  1.000  1.000  0.500  1.0
  Ni  Ni9  1  0.500  0.500  1.000  1.0
  Se  Se10  1  0.389  0.727  0.277  1.0
  Se  Se11  1  0.277  0.606  0.389  1.0
  Se  Se12  1  0.727  0.389  0.606  1.0
  Se  Se13  1  0.606  0.277  0.727  1.0
  Se  Se14  1  0.861  0.523  0.973  1.0
  Se  Se15  1  0.973  0.644  0.861  1.0
  Se  Se16  1  0.523  0.861  0.644  1.0
  Se  Se17  1  0.644  0.973  0.523  1.0
[/CIF]
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