The compound described by Ca(NiO2)2 is Spinel structured and crystallizes in the tetragonal I4_1/a space group. Ca(1) is bonded to four equivalent O(1) atoms to form CaO4 tetrahedra that share corners with twelve equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-69°. Ni(1) is bonded to six equivalent O(1) atoms to form distorted NiO6 octahedra that share corners with six equivalent Ca(1)O4 tetrahedra and edges with six equivalent Ni(1)O6 octahedra. O(1) is bonded to one Ca(1) and three equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing OCaNi3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.086
_cell_length_b   6.086
_cell_length_c   6.086
_cell_angle_alpha   118.197
_cell_angle_beta   118.197
_cell_angle_gamma   93.152
_symmetry_Int_Tables_number   1
_cell_volume   163.453
_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
  Ca  Ca0  1  0.750  0.250  0.500  1.0
  Ca  Ca1  1  0.000  0.000  0.000  1.0
  Ni  Ni2  1  0.375  0.125  0.750  1.0
  Ni  Ni3  1  0.375  0.625  0.250  1.0
  Ni  Ni4  1  0.875  0.625  0.250  1.0
  Ni  Ni5  1  0.375  0.625  0.750  1.0
  O  O6  1  0.113  0.860  0.676  1.0
  O  O7  1  0.563  0.887  0.747  1.0
  O  O8  1  0.140  0.816  0.253  1.0
  O  O9  1  0.566  0.813  0.176  1.0
  O  O10  1  0.610  0.434  0.247  1.0
  O  O11  1  0.187  0.363  0.753  1.0
  O  O12  1  0.184  0.437  0.324  1.0
  O  O13  1  0.637  0.390  0.824  1.0
[/CIF]
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The compound described by Ca(NiO2)2 is Spinel structured and crystallizes in the tetragonal I4_1/a space group. Ca(1) is bonded to four equivalent O(1) atoms to form CaO4 tetrahedra that share corners with twelve equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-69°. Ni(1) is bonded to six equivalent O(1) atoms to form distorted NiO6 octahedra that share corners with six equivalent Ca(1)O4 tetrahedra and edges with six equivalent Ni(1)O6 octahedra. O(1) is bonded to one Ca(1) and three equivalent Ni(1) atoms to form a mixture of distorted corner and edge-sharing OCaNi3 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca(NiO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.086
_cell_length_b   6.086
_cell_length_c   6.086
_cell_angle_alpha   118.197
_cell_angle_beta   118.197
_cell_angle_gamma   93.152
_symmetry_Int_Tables_number   1
_cell_volume   163.453
_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
  Ca  Ca0  1  0.750  0.250  0.500  1.0
  Ca  Ca1  1  0.000  0.000  0.000  1.0
  Ni  Ni2  1  0.375  0.125  0.750  1.0
  Ni  Ni3  1  0.375  0.625  0.250  1.0
  Ni  Ni4  1  0.875  0.625  0.250  1.0
  Ni  Ni5  1  0.375  0.625  0.750  1.0
  O  O6  1  0.113  0.860  0.676  1.0
  O  O7  1  0.563  0.887  0.747  1.0
  O  O8  1  0.140  0.816  0.253  1.0
  O  O9  1  0.566  0.813  0.176  1.0
  O  O10  1  0.610  0.434  0.247  1.0
  O  O11  1  0.187  0.363  0.753  1.0
  O  O12  1  0.184  0.437  0.324  1.0
  O  O13  1  0.637  0.390  0.824  1.0
[/CIF]
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