The material described by CuNi2(PO4)2 crystallizes in the monoclinic P2_1/c space group. Ni(1) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form NiO5 trigonal bipyramids that share corners with five equivalent P(1)O4 tetrahedra and  an edgeedge with one Ni(1)O5 trigonal bipyramid. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with five equivalent Ni(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ni(1), one Cu(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ni(1), one Cu(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CuNi2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.578
_cell_length_b   4.730
_cell_length_c   7.984
_cell_angle_alpha   54.160
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   293.282
_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
  Cu  Cu0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.500  0.000  0.500  1.0
  Ni  Ni2  1  0.626  0.175  0.852  1.0
  Ni  Ni3  1  0.126  0.825  0.648  1.0
  Ni  Ni4  1  0.374  0.825  0.148  1.0
  Ni  Ni5  1  0.874  0.175  0.352  1.0
  P  P6  1  0.824  0.660  0.850  1.0
  P  P7  1  0.324  0.340  0.650  1.0
  P  P8  1  0.176  0.340  0.150  1.0
  P  P9  1  0.676  0.660  0.350  1.0
  O  O10  1  0.889  0.613  0.046  1.0
  O  O11  1  0.389  0.387  0.454  1.0
  O  O12  1  0.111  0.387  0.954  1.0
  O  O13  1  0.611  0.613  0.546  1.0
  O  O14  1  0.673  0.785  0.825  1.0
  O  O15  1  0.173  0.215  0.675  1.0
  O  O16  1  0.327  0.215  0.175  1.0
  O  O17  1  0.827  0.785  0.325  1.0
  O  O18  1  0.918  0.916  0.660  1.0
  O  O19  1  0.418  0.084  0.840  1.0
  O  O20  1  0.324  0.702  0.615  1.0
  O  O21  1  0.824  0.298  0.885  1.0
  O  O22  1  0.676  0.298  0.385  1.0
  O  O23  1  0.176  0.702  0.115  1.0
  O  O24  1  0.582  0.916  0.160  1.0
  O  O25  1  0.082  0.084  0.340  1.0
[/CIF]
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The material described by CuNi2(PO4)2 crystallizes in the monoclinic P2_1/c space group. Ni(1) is bonded to one O(1), one O(2), one O(4), and two equivalent O(3) atoms to form NiO5 trigonal bipyramids that share corners with five equivalent P(1)O4 tetrahedra and  an edgeedge with one Ni(1)O5 trigonal bipyramid. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(4) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with five equivalent Ni(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ni(1), one Cu(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Ni(1), one Cu(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CuNi2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.578
_cell_length_b   4.730
_cell_length_c   7.984
_cell_angle_alpha   54.160
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   293.282
_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
  Cu  Cu0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.500  0.000  0.500  1.0
  Ni  Ni2  1  0.626  0.175  0.852  1.0
  Ni  Ni3  1  0.126  0.825  0.648  1.0
  Ni  Ni4  1  0.374  0.825  0.148  1.0
  Ni  Ni5  1  0.874  0.175  0.352  1.0
  P  P6  1  0.824  0.660  0.850  1.0
  P  P7  1  0.324  0.340  0.650  1.0
  P  P8  1  0.176  0.340  0.150  1.0
  P  P9  1  0.676  0.660  0.350  1.0
  O  O10  1  0.889  0.613  0.046  1.0
  O  O11  1  0.389  0.387  0.454  1.0
  O  O12  1  0.111  0.387  0.954  1.0
  O  O13  1  0.611  0.613  0.546  1.0
  O  O14  1  0.673  0.785  0.825  1.0
  O  O15  1  0.173  0.215  0.675  1.0
  O  O16  1  0.327  0.215  0.175  1.0
  O  O17  1  0.827  0.785  0.325  1.0
  O  O18  1  0.918  0.916  0.660  1.0
  O  O19  1  0.418  0.084  0.840  1.0
  O  O20  1  0.324  0.702  0.615  1.0
  O  O21  1  0.824  0.298  0.885  1.0
  O  O22  1  0.676  0.298  0.385  1.0
  O  O23  1  0.176  0.702  0.115  1.0
  O  O24  1  0.582  0.916  0.160  1.0
  O  O25  1  0.082  0.084  0.340  1.0
[/CIF]
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