The structure described by CaNiP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Ni(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-60°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ni(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Ni(1), and one P(2) atom. is represented by the CIF file [CIF]
data_CaNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.459
_cell_length_b   6.560
_cell_length_c   6.692
_cell_angle_alpha   113.695
_cell_angle_beta   87.339
_cell_angle_gamma   97.454
_symmetry_Int_Tables_number   1
_cell_volume   257.487
_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
  Ca  Ca0  1  0.143  0.271  0.826  1.0
  Ca  Ca1  1  0.857  0.729  0.174  1.0
  Ni  Ni2  1  0.352  0.100  0.224  1.0
  Ni  Ni3  1  0.648  0.900  0.776  1.0
  P  P4  1  0.857  0.229  0.248  1.0
  P  P5  1  0.143  0.771  0.752  1.0
  P  P6  1  0.374  0.642  0.332  1.0
  P  P7  1  0.626  0.358  0.668  1.0
  O  O8  1  0.222  0.610  0.520  1.0
  O  O9  1  0.778  0.390  0.480  1.0
  O  O10  1  0.027  0.101  0.279  1.0
  O  O11  1  0.973  0.899  0.721  1.0
  O  O12  1  0.411  0.254  0.562  1.0
  O  O13  1  0.589  0.746  0.438  1.0
  O  O14  1  0.625  0.599  0.838  1.0
  O  O15  1  0.375  0.401  0.162  1.0
  O  O16  1  0.068  0.616  0.863  1.0
  O  O17  1  0.932  0.384  0.137  1.0
  O  O18  1  0.331  0.950  0.867  1.0
  O  O19  1  0.669  0.050  0.133  1.0
  O  O20  1  0.727  0.205  0.746  1.0
  O  O21  1  0.273  0.795  0.254  1.0
[/CIF]
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The structure described by CaNiP2O7 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(7), and two equivalent O(5) atoms. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(7), and two equivalent O(6) atoms to form NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Ni(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-60°. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 42-55°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Ca(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Ni(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ca(1), one Ni(1), and one P(2) atom. is represented by the CIF file [CIF]
data_CaNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.459
_cell_length_b   6.560
_cell_length_c   6.692
_cell_angle_alpha   113.695
_cell_angle_beta   87.339
_cell_angle_gamma   97.454
_symmetry_Int_Tables_number   1
_cell_volume   257.487
_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
  Ca  Ca0  1  0.143  0.271  0.826  1.0
  Ca  Ca1  1  0.857  0.729  0.174  1.0
  Ni  Ni2  1  0.352  0.100  0.224  1.0
  Ni  Ni3  1  0.648  0.900  0.776  1.0
  P  P4  1  0.857  0.229  0.248  1.0
  P  P5  1  0.143  0.771  0.752  1.0
  P  P6  1  0.374  0.642  0.332  1.0
  P  P7  1  0.626  0.358  0.668  1.0
  O  O8  1  0.222  0.610  0.520  1.0
  O  O9  1  0.778  0.390  0.480  1.0
  O  O10  1  0.027  0.101  0.279  1.0
  O  O11  1  0.973  0.899  0.721  1.0
  O  O12  1  0.411  0.254  0.562  1.0
  O  O13  1  0.589  0.746  0.438  1.0
  O  O14  1  0.625  0.599  0.838  1.0
  O  O15  1  0.375  0.401  0.162  1.0
  O  O16  1  0.068  0.616  0.863  1.0
  O  O17  1  0.932  0.384  0.137  1.0
  O  O18  1  0.331  0.950  0.867  1.0
  O  O19  1  0.669  0.050  0.133  1.0
  O  O20  1  0.727  0.205  0.746  1.0
  O  O21  1  0.273  0.795  0.254  1.0
[/CIF]
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