The material described by Ni15O16 crystallizes in the trigonal R-3m space group. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the third Ni site, Ni(3) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the fourth Ni site, Ni(4) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. In the fifth Ni site, Ni(5) is bonded to six equivalent O(1) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ni(4), one Ni(5), two equivalent Ni(1), and two equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(1)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids,  an edgeedge with one O(3)Ni6 octahedra, edges with three equivalent O(4)Ni6 octahedra, edges with six equivalent O(1)Ni6 octahedra, and edges with two equivalent O(2)Ni5 square pyramids. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Ni(4), two equivalent Ni(2), and two equivalent Ni(3) atoms to form ONi5 square pyramids that share corners with three equivalent O(1)Ni6 octahedra, corners with six equivalent O(2)Ni5 square pyramids,  an edgeedge with one O(4)Ni6 octahedra, edges with two equivalent O(1)Ni6 octahedra, edges with three equivalent O(3)Ni6 octahedra, and edges with two equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 1-6°. In the third O site, O(3) is bonded to three equivalent Ni(2) and three equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(4)Ni6 octahedra, edges with three equivalent O(1)Ni6 octahedra, and edges with nine equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to three equivalent Ni(1) and three equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(4)Ni6 octahedra, edges with nine equivalent O(1)Ni6 octahedra, and edges with three equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 0-4°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni15O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.280
_cell_length_b   10.280
_cell_length_c   10.280
_cell_angle_alpha   33.623
_cell_angle_beta   33.623
_cell_angle_gamma   33.623
_symmetry_Int_Tables_number   1
_cell_volume   296.738
_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  0.000  0.000  0.500  1.0
  Ni  Ni1  1  0.000  0.500  0.500  1.0
  Ni  Ni2  1  0.756  0.246  0.756  1.0
  Ni  Ni3  1  0.750  0.750  0.750  1.0
  Ni  Ni4  1  0.000  0.500  0.000  1.0
  Ni  Ni5  1  0.500  0.000  0.000  1.0
  Ni  Ni6  1  0.500  0.500  0.000  1.0
  Ni  Ni7  1  0.756  0.756  0.246  1.0
  Ni  Ni8  1  0.250  0.250  0.250  1.0
  Ni  Ni9  1  0.754  0.244  0.244  1.0
  Ni  Ni10  1  0.244  0.754  0.244  1.0
  Ni  Ni11  1  0.500  0.500  0.500  1.0
  Ni  Ni12  1  0.500  0.000  0.500  1.0
  Ni  Ni13  1  0.246  0.756  0.756  1.0
  Ni  Ni14  1  0.244  0.244  0.754  1.0
  O  O15  1  0.873  0.376  0.376  1.0
  O  O16  1  0.868  0.868  0.397  1.0
  O  O17  1  0.625  0.625  0.625  1.0
  O  O18  1  0.624  0.127  0.624  1.0
  O  O19  1  0.875  0.875  0.875  1.0
  O  O20  1  0.376  0.376  0.873  1.0
  O  O21  1  0.397  0.868  0.868  1.0
  O  O22  1  0.868  0.397  0.868  1.0
  O  O23  1  0.132  0.603  0.132  1.0
  O  O24  1  0.603  0.132  0.132  1.0
  O  O25  1  0.125  0.125  0.125  1.0
  O  O26  1  0.624  0.624  0.127  1.0
  O  O27  1  0.376  0.873  0.376  1.0
  O  O28  1  0.375  0.375  0.375  1.0
  O  O29  1  0.132  0.132  0.603  1.0
  O  O30  1  0.127  0.624  0.624  1.0
[/CIF]
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The material described by Ni15O16 crystallizes in the trigonal R-3m space group. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the third Ni site, Ni(3) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 2-8°. In the fourth Ni site, Ni(4) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. In the fifth Ni site, Ni(5) is bonded to six equivalent O(1) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ni(4), one Ni(5), two equivalent Ni(1), and two equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(1)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids,  an edgeedge with one O(3)Ni6 octahedra, edges with three equivalent O(4)Ni6 octahedra, edges with six equivalent O(1)Ni6 octahedra, and edges with two equivalent O(2)Ni5 square pyramids. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Ni(4), two equivalent Ni(2), and two equivalent Ni(3) atoms to form ONi5 square pyramids that share corners with three equivalent O(1)Ni6 octahedra, corners with six equivalent O(2)Ni5 square pyramids,  an edgeedge with one O(4)Ni6 octahedra, edges with two equivalent O(1)Ni6 octahedra, edges with three equivalent O(3)Ni6 octahedra, and edges with two equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 1-6°. In the third O site, O(3) is bonded to three equivalent Ni(2) and three equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(4)Ni6 octahedra, edges with three equivalent O(1)Ni6 octahedra, and edges with nine equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to three equivalent Ni(1) and three equivalent Ni(3) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(4)Ni6 octahedra, edges with nine equivalent O(1)Ni6 octahedra, and edges with three equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 0-4°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ni15O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.280
_cell_length_b   10.280
_cell_length_c   10.280
_cell_angle_alpha   33.623
_cell_angle_beta   33.623
_cell_angle_gamma   33.623
_symmetry_Int_Tables_number   1
_cell_volume   296.738
_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  0.000  0.000  0.500  1.0
  Ni  Ni1  1  0.000  0.500  0.500  1.0
  Ni  Ni2  1  0.756  0.246  0.756  1.0
  Ni  Ni3  1  0.750  0.750  0.750  1.0
  Ni  Ni4  1  0.000  0.500  0.000  1.0
  Ni  Ni5  1  0.500  0.000  0.000  1.0
  Ni  Ni6  1  0.500  0.500  0.000  1.0
  Ni  Ni7  1  0.756  0.756  0.246  1.0
  Ni  Ni8  1  0.250  0.250  0.250  1.0
  Ni  Ni9  1  0.754  0.244  0.244  1.0
  Ni  Ni10  1  0.244  0.754  0.244  1.0
  Ni  Ni11  1  0.500  0.500  0.500  1.0
  Ni  Ni12  1  0.500  0.000  0.500  1.0
  Ni  Ni13  1  0.246  0.756  0.756  1.0
  Ni  Ni14  1  0.244  0.244  0.754  1.0
  O  O15  1  0.873  0.376  0.376  1.0
  O  O16  1  0.868  0.868  0.397  1.0
  O  O17  1  0.625  0.625  0.625  1.0
  O  O18  1  0.624  0.127  0.624  1.0
  O  O19  1  0.875  0.875  0.875  1.0
  O  O20  1  0.376  0.376  0.873  1.0
  O  O21  1  0.397  0.868  0.868  1.0
  O  O22  1  0.868  0.397  0.868  1.0
  O  O23  1  0.132  0.603  0.132  1.0
  O  O24  1  0.603  0.132  0.132  1.0
  O  O25  1  0.125  0.125  0.125  1.0
  O  O26  1  0.624  0.624  0.127  1.0
  O  O27  1  0.376  0.873  0.376  1.0
  O  O28  1  0.375  0.375  0.375  1.0
  O  O29  1  0.132  0.132  0.603  1.0
  O  O30  1  0.127  0.624  0.624  1.0
[/CIF]
.