The compound described by BaNi2V2O8 crystallizes in the trigonal R-3 space group. Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with six equivalent V(1)O4 tetrahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 47°. V(1) is bonded to one O(1) and three equivalent O(2) atoms to form VO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 54-58°. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent V(1)O4 tetrahedra, edges with three equivalent Ni(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to three equivalent Ba(1) and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one V(1), and two equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaV2(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.088
_cell_length_b   5.088
_cell_length_c   8.251
_cell_angle_alpha   107.957
_cell_angle_beta   72.043
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   172.853
_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
  Ba  Ba0  1  0.000  1.000  1.000  1.0
  V  V1  1  0.574  0.426  0.277  1.0
  V  V2  1  0.426  0.574  0.723  1.0
  Ni  Ni3  1  0.169  0.831  0.492  1.0
  Ni  Ni4  1  0.831  0.169  0.508  1.0
  O  O5  1  0.648  0.352  0.057  1.0
  O  O6  1  0.352  0.648  0.943  1.0
  O  O7  1  0.563  0.122  0.345  1.0
  O  O8  1  0.214  0.437  0.345  1.0
  O  O9  1  0.878  0.786  0.345  1.0
  O  O10  1  0.437  0.878  0.655  1.0
  O  O11  1  0.786  0.563  0.655  1.0
  O  O12  1  0.122  0.214  0.655  1.0
[/CIF]
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The compound described by BaNi2V2O8 crystallizes in the trigonal R-3 space group. Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ni(1)O6 octahedra, edges with six equivalent Ba(1)O12 cuboctahedra, edges with six equivalent V(1)O4 tetrahedra, and faces with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles are 47°. V(1) is bonded to one O(1) and three equivalent O(2) atoms to form VO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra and edges with three equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 54-58°. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent V(1)O4 tetrahedra, edges with three equivalent Ni(1)O6 octahedra, and  a faceface with one Ba(1)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to three equivalent Ba(1) and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one V(1), and two equivalent Ni(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaV2(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.088
_cell_length_b   5.088
_cell_length_c   8.251
_cell_angle_alpha   107.957
_cell_angle_beta   72.043
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   172.853
_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
  Ba  Ba0  1  0.000  1.000  1.000  1.0
  V  V1  1  0.574  0.426  0.277  1.0
  V  V2  1  0.426  0.574  0.723  1.0
  Ni  Ni3  1  0.169  0.831  0.492  1.0
  Ni  Ni4  1  0.831  0.169  0.508  1.0
  O  O5  1  0.648  0.352  0.057  1.0
  O  O6  1  0.352  0.648  0.943  1.0
  O  O7  1  0.563  0.122  0.345  1.0
  O  O8  1  0.214  0.437  0.345  1.0
  O  O9  1  0.878  0.786  0.345  1.0
  O  O10  1  0.437  0.878  0.655  1.0
  O  O11  1  0.786  0.563  0.655  1.0
  O  O12  1  0.122  0.214  0.655  1.0
[/CIF]
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