The compound described by NiOCaO crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids, edges with three equivalent Ca(2)O6 octahedra, edges with four equivalent Ca(1)O6 octahedra, and  an edgeedge with one Ni(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 1°. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids, edges with three equivalent Ca(1)O6 octahedra, edges with four equivalent Ca(2)O6 octahedra, and edges with three equivalent Ni(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form distorted NiO4 trigonal pyramids that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids,  an edgeedge with one Ca(1)O6 octahedra, and edges with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ni(2), and two equivalent Ni(1) atoms to form distorted OCaNi3 tetrahedra that share corners with two equivalent O(4)Ca5Ni octahedra, corners with two equivalent O(2)Ca3Ni2 square pyramids, corners with four equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra,  an edgeedge with one O(4)Ca5Ni octahedra, and  an edgeedge with one O(3)Ca3Ni2 square pyramid. The corner-sharing octahedral tilt angles range from 11-85°. In the second O site, O(2) is bonded to three equivalent Ca(2) and two equivalent Ni(2) atoms to form OCa3Ni2 square pyramids that share corners with two equivalent O(4)Ca5Ni octahedra, corners with three equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra, edges with three equivalent O(4)Ca5Ni octahedra, and edges with four equivalent O(2)Ca3Ni2 square pyramids. The corner-sharing octahedral tilt angles are 9°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Ni(1) atoms to form OCa3Ni2 square pyramids that share corners with two equivalent O(4)Ca5Ni octahedra, corners with three equivalent O(2)Ca3Ni2 square pyramids, corners with four equivalent O(1)CaNi3 tetrahedra, edges with three equivalent O(4)Ca5Ni octahedra, edges with two equivalent O(3)Ca3Ni2 square pyramids, and  an edgeedge with one O(1)CaNi3 tetrahedra. The corner-sharing octahedral tilt angles range from 12-13°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Ni(2) atom to form OCa5Ni octahedra that share corners with two equivalent O(2)Ca3Ni2 square pyramids, corners with two equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra, edges with four equivalent O(4)Ca5Ni octahedra, edges with three equivalent O(2)Ca3Ni2 square pyramids, edges with three equivalent O(3)Ca3Ni2 square pyramids, and  an edgeedge with one O(1)CaNi3 tetrahedra. is represented by the CIF card [CIF]
data_CaNiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.118
_cell_length_b   8.104
_cell_length_c   8.355
_cell_angle_alpha   82.614
_cell_angle_beta   89.233
_cell_angle_gamma   88.306
_symmetry_Int_Tables_number   1
_cell_volume   209.260
_cell_formula_units_Z   4
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  0.760  0.212  0.950  1.0
  Ca  Ca1  1  0.240  0.788  0.050  1.0
  Ca  Ca2  1  0.229  0.071  0.322  1.0
  Ca  Ca3  1  0.771  0.929  0.678  1.0
  Ni  Ni4  1  0.336  0.567  0.780  1.0
  Ni  Ni5  1  0.218  0.262  0.614  1.0
  Ni  Ni6  1  0.782  0.738  0.386  1.0
  Ni  Ni7  1  0.664  0.433  0.220  1.0
  O  O8  1  0.106  0.580  0.266  1.0
  O  O9  1  0.280  0.819  0.510  1.0
  O  O10  1  0.720  0.181  0.490  1.0
  O  O11  1  0.894  0.420  0.734  1.0
  O  O12  1  0.763  0.701  0.870  1.0
  O  O13  1  0.264  0.074  0.812  1.0
  O  O14  1  0.237  0.299  0.130  1.0
  O  O15  1  0.736  0.926  0.188  1.0
[/CIF]
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The compound described by NiOCaO crystallizes in the triclinic P-1 space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(4) atoms to form distorted CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids, edges with three equivalent Ca(2)O6 octahedra, edges with four equivalent Ca(1)O6 octahedra, and  an edgeedge with one Ni(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 1°. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids, edges with three equivalent Ca(1)O6 octahedra, edges with four equivalent Ca(2)O6 octahedra, and edges with three equivalent Ni(2)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 1°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a distorted square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), and two equivalent O(2) atoms to form distorted NiO4 trigonal pyramids that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Ni(2)O4 trigonal pyramids,  an edgeedge with one Ca(1)O6 octahedra, and edges with three equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-85°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), one Ni(2), and two equivalent Ni(1) atoms to form distorted OCaNi3 tetrahedra that share corners with two equivalent O(4)Ca5Ni octahedra, corners with two equivalent O(2)Ca3Ni2 square pyramids, corners with four equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra,  an edgeedge with one O(4)Ca5Ni octahedra, and  an edgeedge with one O(3)Ca3Ni2 square pyramid. The corner-sharing octahedral tilt angles range from 11-85°. In the second O site, O(2) is bonded to three equivalent Ca(2) and two equivalent Ni(2) atoms to form OCa3Ni2 square pyramids that share corners with two equivalent O(4)Ca5Ni octahedra, corners with three equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra, edges with three equivalent O(4)Ca5Ni octahedra, and edges with four equivalent O(2)Ca3Ni2 square pyramids. The corner-sharing octahedral tilt angles are 9°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and two equivalent Ni(1) atoms to form OCa3Ni2 square pyramids that share corners with two equivalent O(4)Ca5Ni octahedra, corners with three equivalent O(2)Ca3Ni2 square pyramids, corners with four equivalent O(1)CaNi3 tetrahedra, edges with three equivalent O(4)Ca5Ni octahedra, edges with two equivalent O(3)Ca3Ni2 square pyramids, and  an edgeedge with one O(1)CaNi3 tetrahedra. The corner-sharing octahedral tilt angles range from 12-13°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Ni(2) atom to form OCa5Ni octahedra that share corners with two equivalent O(2)Ca3Ni2 square pyramids, corners with two equivalent O(3)Ca3Ni2 square pyramids, corners with two equivalent O(1)CaNi3 tetrahedra, edges with four equivalent O(4)Ca5Ni octahedra, edges with three equivalent O(2)Ca3Ni2 square pyramids, edges with three equivalent O(3)Ca3Ni2 square pyramids, and  an edgeedge with one O(1)CaNi3 tetrahedra. is represented by the CIF card [CIF]
data_CaNiO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.118
_cell_length_b   8.104
_cell_length_c   8.355
_cell_angle_alpha   82.614
_cell_angle_beta   89.233
_cell_angle_gamma   88.306
_symmetry_Int_Tables_number   1
_cell_volume   209.260
_cell_formula_units_Z   4
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  0.760  0.212  0.950  1.0
  Ca  Ca1  1  0.240  0.788  0.050  1.0
  Ca  Ca2  1  0.229  0.071  0.322  1.0
  Ca  Ca3  1  0.771  0.929  0.678  1.0
  Ni  Ni4  1  0.336  0.567  0.780  1.0
  Ni  Ni5  1  0.218  0.262  0.614  1.0
  Ni  Ni6  1  0.782  0.738  0.386  1.0
  Ni  Ni7  1  0.664  0.433  0.220  1.0
  O  O8  1  0.106  0.580  0.266  1.0
  O  O9  1  0.280  0.819  0.510  1.0
  O  O10  1  0.720  0.181  0.490  1.0
  O  O11  1  0.894  0.420  0.734  1.0
  O  O12  1  0.763  0.701  0.870  1.0
  O  O13  1  0.264  0.074  0.812  1.0
  O  O14  1  0.237  0.299  0.130  1.0
  O  O15  1  0.736  0.926  0.188  1.0
[/CIF]
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