The material described by Ni3(AsO4)2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. As(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AsO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-56°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ni(2) and one As(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ni(1), two equivalent Ni(2), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one As(1) atom. is represented by the CIF card [CIF]
data_Ni3(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.908
_cell_length_b   6.367
_cell_length_c   8.146
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.668
_symmetry_Int_Tables_number   1
_cell_volume   271.374
_cell_formula_units_Z   2
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  0.500  1.000  0.500  1.0
  Ni  Ni1  1  0.117  0.735  0.250  1.0
  Ni  Ni2  1  0.383  0.265  0.750  1.0
  Ni  Ni3  1  0.000  1.000  1.000  1.0
  Ni  Ni4  1  0.883  0.265  0.750  1.0
  Ni  Ni5  1  0.617  0.735  0.250  1.0
  As  As6  1  0.375  0.751  0.884  1.0
  As  As7  1  0.625  0.249  0.116  1.0
  As  As8  1  0.125  0.249  0.384  1.0
  As  As9  1  0.875  0.751  0.616  1.0
  O  O10  1  0.252  0.505  0.764  1.0
  O  O11  1  0.748  0.495  0.236  1.0
  O  O12  1  0.248  0.495  0.264  1.0
  O  O13  1  0.752  0.505  0.736  1.0
  O  O14  1  0.998  0.997  0.749  1.0
  O  O15  1  0.002  0.003  0.251  1.0
  O  O16  1  0.502  0.003  0.249  1.0
  O  O17  1  0.498  0.997  0.751  1.0
  O  O18  1  0.860  0.242  0.999  1.0
  O  O19  1  0.618  0.758  0.001  1.0
  O  O20  1  0.640  0.758  0.499  1.0
  O  O21  1  0.882  0.242  0.501  1.0
  O  O22  1  0.140  0.758  0.001  1.0
  O  O23  1  0.382  0.242  0.999  1.0
  O  O24  1  0.360  0.242  0.501  1.0
  O  O25  1  0.118  0.758  0.499  1.0
[/CIF]
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The material described by Ni3(AsO4)2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra and edges with four equivalent Ni(2)O6 octahedra. In the second Ni site, Ni(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. As(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form AsO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and corners with six equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-56°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ni(2) and one As(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ni(1), two equivalent Ni(2), and one As(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one As(1) atom. is represented by the CIF card [CIF]
data_Ni3(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.908
_cell_length_b   6.367
_cell_length_c   8.146
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   117.668
_symmetry_Int_Tables_number   1
_cell_volume   271.374
_cell_formula_units_Z   2
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  0.500  1.000  0.500  1.0
  Ni  Ni1  1  0.117  0.735  0.250  1.0
  Ni  Ni2  1  0.383  0.265  0.750  1.0
  Ni  Ni3  1  0.000  1.000  1.000  1.0
  Ni  Ni4  1  0.883  0.265  0.750  1.0
  Ni  Ni5  1  0.617  0.735  0.250  1.0
  As  As6  1  0.375  0.751  0.884  1.0
  As  As7  1  0.625  0.249  0.116  1.0
  As  As8  1  0.125  0.249  0.384  1.0
  As  As9  1  0.875  0.751  0.616  1.0
  O  O10  1  0.252  0.505  0.764  1.0
  O  O11  1  0.748  0.495  0.236  1.0
  O  O12  1  0.248  0.495  0.264  1.0
  O  O13  1  0.752  0.505  0.736  1.0
  O  O14  1  0.998  0.997  0.749  1.0
  O  O15  1  0.002  0.003  0.251  1.0
  O  O16  1  0.502  0.003  0.249  1.0
  O  O17  1  0.498  0.997  0.751  1.0
  O  O18  1  0.860  0.242  0.999  1.0
  O  O19  1  0.618  0.758  0.001  1.0
  O  O20  1  0.640  0.758  0.499  1.0
  O  O21  1  0.882  0.242  0.501  1.0
  O  O22  1  0.140  0.758  0.001  1.0
  O  O23  1  0.382  0.242  0.999  1.0
  O  O24  1  0.360  0.242  0.501  1.0
  O  O25  1  0.118  0.758  0.499  1.0
[/CIF]
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