The compound described by NiU2O6 is Hydrophilite-derived structured and crystallizes in the trigonal P321 space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form UO6 octahedra that share corners with four equivalent Ni(2)O6 octahedra, corners with six equivalent U(2)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-52°. In the second U site, U(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form UO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with six equivalent U(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-54°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent U(2)O6 octahedra and edges with three equivalent U(1)O6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Ni site, Ni(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent U(1)O6 octahedra and edges with three equivalent U(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one U(1), one U(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one U(1), one U(2), and one Ni(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one U(1), one U(2), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_U2NiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.151
_cell_length_b   9.151
_cell_length_c   5.029
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   364.685
_cell_formula_units_Z   3
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
  U  U0  1  0.647  0.000  0.000  1.0
  U  U1  1  0.000  0.647  0.000  1.0
  U  U2  1  0.353  0.353  0.000  1.0
  U  U3  1  0.313  0.000  0.500  1.0
  U  U4  1  0.000  0.313  0.500  1.0
  U  U5  1  0.687  0.687  0.500  1.0
  Ni  Ni6  1  0.000  0.000  0.000  1.0
  Ni  Ni7  1  0.333  0.667  0.505  1.0
  Ni  Ni8  1  0.667  0.333  0.495  1.0
  O  O9  1  0.100  0.878  0.777  1.0
  O  O10  1  0.122  0.223  0.777  1.0
  O  O11  1  0.777  0.900  0.777  1.0
  O  O12  1  0.223  0.122  0.223  1.0
  O  O13  1  0.900  0.777  0.223  1.0
  O  O14  1  0.878  0.100  0.223  1.0
  O  O15  1  0.455  0.567  0.735  1.0
  O  O16  1  0.433  0.888  0.735  1.0
  O  O17  1  0.112  0.545  0.735  1.0
  O  O18  1  0.888  0.433  0.265  1.0
  O  O19  1  0.545  0.112  0.265  1.0
  O  O20  1  0.567  0.455  0.265  1.0
  O  O21  1  0.220  0.775  0.274  1.0
  O  O22  1  0.225  0.445  0.274  1.0
  O  O23  1  0.555  0.780  0.274  1.0
  O  O24  1  0.445  0.225  0.726  1.0
  O  O25  1  0.780  0.555  0.726  1.0
  O  O26  1  0.775  0.220  0.726  1.0
[/CIF]
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The compound described by NiU2O6 is Hydrophilite-derived structured and crystallizes in the trigonal P321 space group. There are two inequivalent U sites. In the first U site, U(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form UO6 octahedra that share corners with four equivalent Ni(2)O6 octahedra, corners with six equivalent U(2)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-52°. In the second U site, U(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form UO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with six equivalent U(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-54°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to six equivalent O(1) atoms to form NiO6 octahedra that share corners with six equivalent U(2)O6 octahedra and edges with three equivalent U(1)O6 octahedra. The corner-sharing octahedral tilt angles are 54°. In the second Ni site, Ni(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent U(1)O6 octahedra and edges with three equivalent U(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-52°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one U(1), one U(2), and one Ni(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one U(1), one U(2), and one Ni(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one U(1), one U(2), and one Ni(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_U2NiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.151
_cell_length_b   9.151
_cell_length_c   5.029
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   364.685
_cell_formula_units_Z   3
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
  U  U0  1  0.647  0.000  0.000  1.0
  U  U1  1  0.000  0.647  0.000  1.0
  U  U2  1  0.353  0.353  0.000  1.0
  U  U3  1  0.313  0.000  0.500  1.0
  U  U4  1  0.000  0.313  0.500  1.0
  U  U5  1  0.687  0.687  0.500  1.0
  Ni  Ni6  1  0.000  0.000  0.000  1.0
  Ni  Ni7  1  0.333  0.667  0.505  1.0
  Ni  Ni8  1  0.667  0.333  0.495  1.0
  O  O9  1  0.100  0.878  0.777  1.0
  O  O10  1  0.122  0.223  0.777  1.0
  O  O11  1  0.777  0.900  0.777  1.0
  O  O12  1  0.223  0.122  0.223  1.0
  O  O13  1  0.900  0.777  0.223  1.0
  O  O14  1  0.878  0.100  0.223  1.0
  O  O15  1  0.455  0.567  0.735  1.0
  O  O16  1  0.433  0.888  0.735  1.0
  O  O17  1  0.112  0.545  0.735  1.0
  O  O18  1  0.888  0.433  0.265  1.0
  O  O19  1  0.545  0.112  0.265  1.0
  O  O20  1  0.567  0.455  0.265  1.0
  O  O21  1  0.220  0.775  0.274  1.0
  O  O22  1  0.225  0.445  0.274  1.0
  O  O23  1  0.555  0.780  0.274  1.0
  O  O24  1  0.445  0.225  0.726  1.0
  O  O25  1  0.780  0.555  0.726  1.0
  O  O26  1  0.775  0.220  0.726  1.0
[/CIF]
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