The structure described by NiP2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(12), one O(18), one O(21), one O(27), one O(5), and one O(7) atom to form NiO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the second Ni site, Ni(2) is bonded to one O(14), one O(15), one O(16), one O(20), one O(22), and one O(8) atom to form NiO6 octahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  an edgeedge with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the third Ni site, Ni(3) is bonded to one O(1), one O(11), one O(12), one O(17), one O(26), and one O(4) atom to form NiO6 octahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  an edgeedge with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the fourth Ni site, Ni(4) is bonded to one O(13), one O(19), one O(20), one O(25), one O(28), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and corners with two equivalent P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(18), one O(23), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the second P site, P(2) is bonded to one O(2), one O(24), one O(25), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-54°. In the third P site, P(3) is bonded to one O(11), one O(16), one O(24), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-48°. In the fourth P site, P(4) is bonded to one O(10), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-49°. In the fifth P site, P(5) is bonded to one O(10), one O(20), one O(21), and one O(22) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. In the sixth P site, P(6) is bonded to one O(13), one O(15), one O(19), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(4)O6 octahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-49°. In the seventh P site, P(7) is bonded to one O(14), one O(17), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the eighth P site, P(8) is bonded to one O(12), one O(26), one O(28), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one P(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one P(7) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ni(3) and one P(4) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(4) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one P(6) and one P(8) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ni(4) and one P(7) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one P(4) and one P(5) atom. In the eleventh O site, O(11) is bonded in a distorted bent 120 degrees geometry to one Ni(3) and one P(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(3), and one P(8) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to one Ni(4) and one P(6) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(7) atom. In the fifteenth O site, O(15) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(6) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Ni(2) and one P(3) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Ni(3) and one P(7) atom. In the eighteenth O site, O(18) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the nineteenth O site, O(19) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(6) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(4), and one P(5) atom. In the twenty-first O site, O(21) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(5) atom. In the twenty-second O site, O(22) is bonded in an L-shaped geometry to one Ni(2) and one P(5) atom. In the twenty-third O site, O(23) is bonded in a single-bond geometry to one P(1) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the twenty-fifth O site, O(25) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(2) atom. In the twenty-sixth O site, O(26) is bonded in an L-shaped geometry to one Ni(3) and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(3) atom. In the twenty-eighth O site, O(28) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(8) atom. is represented by the CIF card [CIF]
data_NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.173
_cell_length_b   10.583
_cell_length_c   9.016
_cell_angle_alpha   63.499
_cell_angle_beta   106.275
_cell_angle_gamma   94.850
_symmetry_Int_Tables_number   1
_cell_volume   505.469
_cell_formula_units_Z   4
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  0.377  0.254  0.503  1.0
  Ni  Ni1  1  0.705  0.779  0.097  1.0
  Ni  Ni2  1  0.296  0.225  0.894  1.0
  Ni  Ni3  1  0.621  0.751  0.487  1.0
  P  P4  1  0.091  0.218  0.182  1.0
  P  P5  1  0.909  0.787  0.807  1.0
  P  P6  1  0.296  0.970  0.807  1.0
  P  P7  1  0.898  0.299  0.556  1.0
  P  P8  1  0.584  0.539  0.298  1.0
  P  P9  1  0.100  0.705  0.435  1.0
  P  P10  1  0.705  0.034  0.183  1.0
  P  P11  1  0.415  0.466  0.693  1.0
  O  O12  1  0.152  0.158  0.069  1.0
  O  O13  1  0.035  0.649  0.888  1.0
  O  O14  1  0.936  0.084  0.272  1.0
  O  O15  1  0.002  0.283  0.739  1.0
  O  O16  1  0.689  0.214  0.533  1.0
  O  O17  1  0.196  0.542  0.542  1.0
  O  O18  1  0.059  0.272  0.469  1.0
  O  O19  1  0.851  0.845  0.923  1.0
  O  O20  1  0.594  0.943  0.326  1.0
  O  O21  1  0.802  0.463  0.451  1.0
  O  O22  1  0.254  0.040  0.914  1.0
  O  O23  1  0.438  0.315  0.698  1.0
  O  O24  1  0.939  0.734  0.519  1.0
  O  O25  1  0.749  0.964  0.078  1.0
  O  O26  1  0.997  0.720  0.252  1.0
  O  O27  1  0.429  0.827  0.928  1.0
  O  O28  1  0.573  0.178  0.062  1.0
  O  O29  1  0.316  0.193  0.326  1.0
  O  O30  1  0.309  0.791  0.457  1.0
  O  O31  1  0.560  0.691  0.292  1.0
  O  O32  1  0.382  0.448  0.333  1.0
  O  O33  1  0.639  0.588  0.124  1.0
  O  O34  1  0.964  0.356  0.099  1.0
  O  O35  1  0.064  0.921  0.719  1.0
  O  O36  1  0.684  0.813  0.664  1.0
  O  O37  1  0.361  0.415  0.868  1.0
  O  O38  1  0.404  0.063  0.663  1.0
  O  O39  1  0.616  0.557  0.658  1.0
[/CIF]
.
The structure described by NiP2O7 crystallizes in the triclinic P1 space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(12), one O(18), one O(21), one O(27), one O(5), and one O(7) atom to form NiO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and corners with two equivalent P(4)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the second Ni site, Ni(2) is bonded to one O(14), one O(15), one O(16), one O(20), one O(22), and one O(8) atom to form NiO6 octahedra that share  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(6)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  an edgeedge with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the third Ni site, Ni(3) is bonded to one O(1), one O(11), one O(12), one O(17), one O(26), and one O(4) atom to form NiO6 octahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra, and  an edgeedge with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. In the fourth Ni site, Ni(4) is bonded to one O(13), one O(19), one O(20), one O(25), one O(28), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(5)O4 tetrahedra,  a cornercorner with one P(7)O4 tetrahedra,  a cornercorner with one P(8)O4 tetrahedra, and corners with two equivalent P(6)O4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are eight inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(18), one O(23), and one O(3) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, and  a cornercorner with one P(7)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-53°. In the second P site, P(2) is bonded to one O(2), one O(24), one O(25), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-54°. In the third P site, P(3) is bonded to one O(11), one O(16), one O(24), and one O(27) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 44-48°. In the fourth P site, P(4) is bonded to one O(10), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, and  a cornercorner with one P(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-49°. In the fifth P site, P(5) is bonded to one O(10), one O(20), one O(21), and one O(22) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(4)O4 tetrahedra, and  an edgeedge with one Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. In the sixth P site, P(6) is bonded to one O(13), one O(15), one O(19), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(4)O6 octahedra, and  a cornercorner with one P(8)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-49°. In the seventh P site, P(7) is bonded to one O(14), one O(17), one O(3), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the eighth P site, P(8) is bonded to one O(12), one O(26), one O(28), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra,  a cornercorner with one P(6)O4 tetrahedra, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. There are twenty-eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one P(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one P(7) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ni(3) and one P(4) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(4) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one P(6) and one P(8) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one Ni(4) and one P(7) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one P(4) and one P(5) atom. In the eleventh O site, O(11) is bonded in a distorted bent 120 degrees geometry to one Ni(3) and one P(3) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(3), and one P(8) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to one Ni(4) and one P(6) atom. In the fourteenth O site, O(14) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(7) atom. In the fifteenth O site, O(15) is bonded in a distorted bent 120 degrees geometry to one Ni(2) and one P(6) atom. In the sixteenth O site, O(16) is bonded in a bent 120 degrees geometry to one Ni(2) and one P(3) atom. In the seventeenth O site, O(17) is bonded in a bent 120 degrees geometry to one Ni(3) and one P(7) atom. In the eighteenth O site, O(18) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the nineteenth O site, O(19) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(6) atom. In the twentieth O site, O(20) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(4), and one P(5) atom. In the twenty-first O site, O(21) is bonded in a bent 120 degrees geometry to one Ni(1) and one P(5) atom. In the twenty-second O site, O(22) is bonded in an L-shaped geometry to one Ni(2) and one P(5) atom. In the twenty-third O site, O(23) is bonded in a single-bond geometry to one P(1) atom. In the twenty-fourth O site, O(24) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the twenty-fifth O site, O(25) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(2) atom. In the twenty-sixth O site, O(26) is bonded in an L-shaped geometry to one Ni(3) and one P(8) atom. In the twenty-seventh O site, O(27) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(3) atom. In the twenty-eighth O site, O(28) is bonded in a bent 120 degrees geometry to one Ni(4) and one P(8) atom. is represented by the CIF card [CIF]
data_NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.173
_cell_length_b   10.583
_cell_length_c   9.016
_cell_angle_alpha   63.499
_cell_angle_beta   106.275
_cell_angle_gamma   94.850
_symmetry_Int_Tables_number   1
_cell_volume   505.469
_cell_formula_units_Z   4
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  0.377  0.254  0.503  1.0
  Ni  Ni1  1  0.705  0.779  0.097  1.0
  Ni  Ni2  1  0.296  0.225  0.894  1.0
  Ni  Ni3  1  0.621  0.751  0.487  1.0
  P  P4  1  0.091  0.218  0.182  1.0
  P  P5  1  0.909  0.787  0.807  1.0
  P  P6  1  0.296  0.970  0.807  1.0
  P  P7  1  0.898  0.299  0.556  1.0
  P  P8  1  0.584  0.539  0.298  1.0
  P  P9  1  0.100  0.705  0.435  1.0
  P  P10  1  0.705  0.034  0.183  1.0
  P  P11  1  0.415  0.466  0.693  1.0
  O  O12  1  0.152  0.158  0.069  1.0
  O  O13  1  0.035  0.649  0.888  1.0
  O  O14  1  0.936  0.084  0.272  1.0
  O  O15  1  0.002  0.283  0.739  1.0
  O  O16  1  0.689  0.214  0.533  1.0
  O  O17  1  0.196  0.542  0.542  1.0
  O  O18  1  0.059  0.272  0.469  1.0
  O  O19  1  0.851  0.845  0.923  1.0
  O  O20  1  0.594  0.943  0.326  1.0
  O  O21  1  0.802  0.463  0.451  1.0
  O  O22  1  0.254  0.040  0.914  1.0
  O  O23  1  0.438  0.315  0.698  1.0
  O  O24  1  0.939  0.734  0.519  1.0
  O  O25  1  0.749  0.964  0.078  1.0
  O  O26  1  0.997  0.720  0.252  1.0
  O  O27  1  0.429  0.827  0.928  1.0
  O  O28  1  0.573  0.178  0.062  1.0
  O  O29  1  0.316  0.193  0.326  1.0
  O  O30  1  0.309  0.791  0.457  1.0
  O  O31  1  0.560  0.691  0.292  1.0
  O  O32  1  0.382  0.448  0.333  1.0
  O  O33  1  0.639  0.588  0.124  1.0
  O  O34  1  0.964  0.356  0.099  1.0
  O  O35  1  0.064  0.921  0.719  1.0
  O  O36  1  0.684  0.813  0.664  1.0
  O  O37  1  0.361  0.415  0.868  1.0
  O  O38  1  0.404  0.063  0.663  1.0
  O  O39  1  0.616  0.557  0.658  1.0
[/CIF]
.