The crystal structure described by Ni15O16 crystallizes in the trigonal R-3m space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Ni(2)O6 octahedra, corners with three equivalent Ni(4)O4 trigonal pyramids,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(6)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(5)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(4) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the third Ni site, Ni(3) is bonded to six equivalent O(4) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Ni site, Ni(4) is bonded to one O(1) and three equivalent O(2) atoms to form a mixture of distorted corner and face-sharing NiO4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-71°. In the fifth Ni site, Ni(5) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Ni(3)O6 octahedra, corners with three equivalent Ni(6)O6 octahedra, edges with three equivalent Ni(2)O6 octahedra, edges with six equivalent Ni(1)O6 octahedra, and  a faceface with one Ni(4)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 0-1°. In the sixth Ni site, Ni(6) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Ni(5)O6 octahedra, corners with six equivalent Ni(4)O4 trigonal pyramids, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ni(4) and three equivalent Ni(1) atoms to form ONi4 tetrahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with nine equivalent O(2)Ni5 square pyramids, and edges with three equivalent O(4)Ni6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the second O site, O(2) is bonded to one Ni(4), one Ni(5), one Ni(6), and two equivalent Ni(1) atoms to form ONi5 square pyramids that share corners with three equivalent O(4)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids, corners with three equivalent O(1)Ni4 tetrahedra,  an edgeedge with one O(3)Ni6 octahedra, edges with two equivalent O(4)Ni6 octahedra, and edges with four equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 4-5°. In the third O site, O(3) is bonded to three equivalent Ni(1) and three equivalent Ni(2) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(1)Ni4 tetrahedra, edges with nine equivalent O(4)Ni6 octahedra, and edges with three equivalent O(2)Ni5 square pyramids. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to one Ni(3), one Ni(5), two equivalent Ni(1), and two equivalent Ni(2) atoms to form ONi6 octahedra that share corners with three equivalent O(4)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids, edges with three equivalent O(3)Ni6 octahedra, edges with six equivalent O(4)Ni6 octahedra, edges with two equivalent O(2)Ni5 square pyramids, and  an edgeedge with one O(1)Ni4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Ni15O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.694
_cell_length_b   10.694
_cell_length_c   10.694
_cell_angle_alpha   32.048
_cell_angle_beta   32.048
_cell_angle_gamma   32.048
_symmetry_Int_Tables_number   1
_cell_volume   305.992
_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  0.248  0.750  0.248  1.0
  Ni  Ni1  1  0.500  0.000  0.000  1.0
  Ni  Ni2  1  0.752  0.250  0.752  1.0
  Ni  Ni3  1  0.752  0.752  0.250  1.0
  Ni  Ni4  1  0.248  0.248  0.750  1.0
  Ni  Ni5  1  0.500  0.500  0.500  1.0
  Ni  Ni6  1  0.676  0.676  0.676  1.0
  Ni  Ni7  1  0.750  0.248  0.248  1.0
  Ni  Ni8  1  0.000  0.500  0.000  1.0
  Ni  Ni9  1  0.250  0.752  0.752  1.0
  Ni  Ni10  1  0.000  0.000  0.500  1.0
  Ni  Ni11  1  0.244  0.244  0.244  1.0
  Ni  Ni12  1  0.756  0.756  0.756  1.0
  Ni  Ni13  1  0.324  0.324  0.324  1.0
  Ni  Ni14  1  0.000  0.000  0.000  1.0
  O  O15  1  0.614  0.614  0.614  1.0
  O  O16  1  0.880  0.880  0.375  1.0
  O  O17  1  0.125  0.125  0.125  1.0
  O  O18  1  0.371  0.371  0.873  1.0
  O  O19  1  0.625  0.120  0.120  1.0
  O  O20  1  0.127  0.629  0.629  1.0
  O  O21  1  0.880  0.375  0.880  1.0
  O  O22  1  0.371  0.873  0.371  1.0
  O  O23  1  0.386  0.386  0.386  1.0
  O  O24  1  0.875  0.875  0.875  1.0
  O  O25  1  0.120  0.120  0.625  1.0
  O  O26  1  0.629  0.629  0.127  1.0
  O  O27  1  0.120  0.625  0.120  1.0
  O  O28  1  0.375  0.880  0.880  1.0
  O  O29  1  0.629  0.127  0.629  1.0
  O  O30  1  0.873  0.371  0.371  1.0
[/CIF]
.
The crystal structure described by Ni15O16 crystallizes in the trigonal R-3m space group. There are six inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Ni(2)O6 octahedra, corners with three equivalent Ni(4)O4 trigonal pyramids,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(6)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(5)O6 octahedra, and edges with four equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(4) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the third Ni site, Ni(3) is bonded to six equivalent O(4) atoms to form a mixture of corner and edge-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Ni site, Ni(4) is bonded to one O(1) and three equivalent O(2) atoms to form a mixture of distorted corner and face-sharing NiO4 trigonal pyramids. The corner-sharing octahedral tilt angles range from 50-71°. In the fifth Ni site, Ni(5) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form NiO6 octahedra that share corners with three equivalent Ni(3)O6 octahedra, corners with three equivalent Ni(6)O6 octahedra, edges with three equivalent Ni(2)O6 octahedra, edges with six equivalent Ni(1)O6 octahedra, and  a faceface with one Ni(4)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 0-1°. In the sixth Ni site, Ni(6) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Ni(5)O6 octahedra, corners with six equivalent Ni(4)O4 trigonal pyramids, and edges with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ni(4) and three equivalent Ni(1) atoms to form ONi4 tetrahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with nine equivalent O(2)Ni5 square pyramids, and edges with three equivalent O(4)Ni6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the second O site, O(2) is bonded to one Ni(4), one Ni(5), one Ni(6), and two equivalent Ni(1) atoms to form ONi5 square pyramids that share corners with three equivalent O(4)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids, corners with three equivalent O(1)Ni4 tetrahedra,  an edgeedge with one O(3)Ni6 octahedra, edges with two equivalent O(4)Ni6 octahedra, and edges with four equivalent O(2)Ni5 square pyramids. The corner-sharing octahedral tilt angles range from 4-5°. In the third O site, O(3) is bonded to three equivalent Ni(1) and three equivalent Ni(2) atoms to form ONi6 octahedra that share corners with three equivalent O(3)Ni6 octahedra, corners with three equivalent O(1)Ni4 tetrahedra, edges with nine equivalent O(4)Ni6 octahedra, and edges with three equivalent O(2)Ni5 square pyramids. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded to one Ni(3), one Ni(5), two equivalent Ni(1), and two equivalent Ni(2) atoms to form ONi6 octahedra that share corners with three equivalent O(4)Ni6 octahedra, corners with three equivalent O(2)Ni5 square pyramids, edges with three equivalent O(3)Ni6 octahedra, edges with six equivalent O(4)Ni6 octahedra, edges with two equivalent O(2)Ni5 square pyramids, and  an edgeedge with one O(1)Ni4 tetrahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Ni15O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.694
_cell_length_b   10.694
_cell_length_c   10.694
_cell_angle_alpha   32.048
_cell_angle_beta   32.048
_cell_angle_gamma   32.048
_symmetry_Int_Tables_number   1
_cell_volume   305.992
_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  0.248  0.750  0.248  1.0
  Ni  Ni1  1  0.500  0.000  0.000  1.0
  Ni  Ni2  1  0.752  0.250  0.752  1.0
  Ni  Ni3  1  0.752  0.752  0.250  1.0
  Ni  Ni4  1  0.248  0.248  0.750  1.0
  Ni  Ni5  1  0.500  0.500  0.500  1.0
  Ni  Ni6  1  0.676  0.676  0.676  1.0
  Ni  Ni7  1  0.750  0.248  0.248  1.0
  Ni  Ni8  1  0.000  0.500  0.000  1.0
  Ni  Ni9  1  0.250  0.752  0.752  1.0
  Ni  Ni10  1  0.000  0.000  0.500  1.0
  Ni  Ni11  1  0.244  0.244  0.244  1.0
  Ni  Ni12  1  0.756  0.756  0.756  1.0
  Ni  Ni13  1  0.324  0.324  0.324  1.0
  Ni  Ni14  1  0.000  0.000  0.000  1.0
  O  O15  1  0.614  0.614  0.614  1.0
  O  O16  1  0.880  0.880  0.375  1.0
  O  O17  1  0.125  0.125  0.125  1.0
  O  O18  1  0.371  0.371  0.873  1.0
  O  O19  1  0.625  0.120  0.120  1.0
  O  O20  1  0.127  0.629  0.629  1.0
  O  O21  1  0.880  0.375  0.880  1.0
  O  O22  1  0.371  0.873  0.371  1.0
  O  O23  1  0.386  0.386  0.386  1.0
  O  O24  1  0.875  0.875  0.875  1.0
  O  O25  1  0.120  0.120  0.625  1.0
  O  O26  1  0.629  0.629  0.127  1.0
  O  O27  1  0.120  0.625  0.120  1.0
  O  O28  1  0.375  0.880  0.880  1.0
  O  O29  1  0.629  0.127  0.629  1.0
  O  O30  1  0.873  0.371  0.371  1.0
[/CIF]
.