The compound described by Sr(NiO2)4 crystallizes in the trigonal R-3m space group. Sr(1) is bonded in a distorted hexagonal planar geometry to six equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form edge-sharing NiO6 octahedra. In the second Ni site, Ni(2) is bonded to six equivalent O(2) atoms to form edge-sharing NiO6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Ni(2), and two equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Sr(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   6.835
_cell_angle_alpha   65.242
_cell_angle_beta   65.243
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   169.837
_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
  Ni  Ni0  1  0.500  0.500  1.000  1.0
  Ni  Ni1  1  1.000  0.500  0.000  1.0
  Ni  Ni2  1  0.500  0.000  0.000  1.0
  Ni  Ni3  1  0.000  1.000  0.000  1.0
  O  O4  1  0.720  0.720  0.839  1.0
  O  O5  1  0.280  0.280  0.161  1.0
  O  O6  1  0.233  0.233  0.833  1.0
  O  O7  1  0.299  0.767  0.167  1.0
  O  O8  1  0.767  0.767  0.167  1.0
  O  O9  1  0.767  0.299  0.167  1.0
  O  O10  1  0.701  0.233  0.833  1.0
  O  O11  1  0.233  0.701  0.833  1.0
  Sr  Sr12  1  0.500  0.500  0.500  1.0
[/CIF]
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The compound described by Sr(NiO2)4 crystallizes in the trigonal R-3m space group. Sr(1) is bonded in a distorted hexagonal planar geometry to six equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form edge-sharing NiO6 octahedra. In the second Ni site, Ni(2) is bonded to six equivalent O(2) atoms to form edge-sharing NiO6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to three equivalent Ni(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Ni(2), and two equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Sr(NiO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   6.835
_cell_angle_alpha   65.242
_cell_angle_beta   65.243
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   169.837
_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
  Ni  Ni0  1  0.500  0.500  1.000  1.0
  Ni  Ni1  1  1.000  0.500  0.000  1.0
  Ni  Ni2  1  0.500  0.000  0.000  1.0
  Ni  Ni3  1  0.000  1.000  0.000  1.0
  O  O4  1  0.720  0.720  0.839  1.0
  O  O5  1  0.280  0.280  0.161  1.0
  O  O6  1  0.233  0.233  0.833  1.0
  O  O7  1  0.299  0.767  0.167  1.0
  O  O8  1  0.767  0.767  0.167  1.0
  O  O9  1  0.767  0.299  0.167  1.0
  O  O10  1  0.701  0.233  0.833  1.0
  O  O11  1  0.233  0.701  0.833  1.0
  Sr  Sr12  1  0.500  0.500  0.500  1.0
[/CIF]
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