The crystal structure described by Ca(NiS2)4 crystallizes in the trigonal R-3m space group. Ca(1) is bonded to six equivalent S(1) atoms to form CaS6 octahedra that share corners with six equivalent Ni(1)S6 octahedra and edges with six equivalent Ni(2)S6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent S(1) atoms to form NiS6 octahedra that share corners with six equivalent Ca(1)S6 octahedra and edges with six equivalent Ni(2)S6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the second Ni site, Ni(2) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form NiS6 octahedra that share edges with two equivalent Ca(1)S6 octahedra, edges with two equivalent Ni(1)S6 octahedra, and edges with four equivalent Ni(2)S6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Ni(1), and two equivalent Ni(2) atoms. In the second S site, S(2) is bonded in a distorted T-shaped geometry to three equivalent Ni(2) atoms. is represented by the CIF card [CIF]
data_Ca(NiS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.918
_cell_length_b   6.918
_cell_length_c   6.918
_cell_angle_alpha   60.523
_cell_angle_beta   60.523
_cell_angle_gamma   60.523
_symmetry_Int_Tables_number   1
_cell_volume   236.844
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.500  0.500  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.500  0.000  0.500  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  S  S5  1  0.729  0.300  0.729  1.0
  S  S6  1  0.729  0.729  0.300  1.0
  S  S7  1  0.300  0.729  0.729  1.0
  S  S8  1  0.735  0.735  0.735  1.0
  S  S9  1  0.265  0.265  0.265  1.0
  S  S10  1  0.271  0.271  0.700  1.0
  S  S11  1  0.700  0.271  0.271  1.0
  S  S12  1  0.271  0.700  0.271  1.0
[/CIF]
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The crystal structure described by Ca(NiS2)4 crystallizes in the trigonal R-3m space group. Ca(1) is bonded to six equivalent S(1) atoms to form CaS6 octahedra that share corners with six equivalent Ni(1)S6 octahedra and edges with six equivalent Ni(2)S6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent S(1) atoms to form NiS6 octahedra that share corners with six equivalent Ca(1)S6 octahedra and edges with six equivalent Ni(2)S6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the second Ni site, Ni(2) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form NiS6 octahedra that share edges with two equivalent Ca(1)S6 octahedra, edges with two equivalent Ni(1)S6 octahedra, and edges with four equivalent Ni(2)S6 octahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Ni(1), and two equivalent Ni(2) atoms. In the second S site, S(2) is bonded in a distorted T-shaped geometry to three equivalent Ni(2) atoms. is represented by the CIF card [CIF]
data_Ca(NiS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.918
_cell_length_b   6.918
_cell_length_c   6.918
_cell_angle_alpha   60.523
_cell_angle_beta   60.523
_cell_angle_gamma   60.523
_symmetry_Int_Tables_number   1
_cell_volume   236.844
_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
  Ca  Ca0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.500  0.500  0.500  1.0
  Ni  Ni2  1  0.500  0.500  0.000  1.0
  Ni  Ni3  1  0.500  0.000  0.500  1.0
  Ni  Ni4  1  0.000  0.500  0.500  1.0
  S  S5  1  0.729  0.300  0.729  1.0
  S  S6  1  0.729  0.729  0.300  1.0
  S  S7  1  0.300  0.729  0.729  1.0
  S  S8  1  0.735  0.735  0.735  1.0
  S  S9  1  0.265  0.265  0.265  1.0
  S  S10  1  0.271  0.271  0.700  1.0
  S  S11  1  0.700  0.271  0.271  1.0
  S  S12  1  0.271  0.700  0.271  1.0
[/CIF]
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