The structure described by MgNiP2O7 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. Ni(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(3) 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  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. is represented by the CIF card [CIF]
data_MgNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.802
_cell_length_b   5.802
_cell_length_c   5.185
_cell_angle_alpha   88.339
_cell_angle_beta   91.668
_cell_angle_gamma   73.379
_symmetry_Int_Tables_number   1
_cell_volume   167.064
_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
  Mg  Mg0  1  0.170  0.170  0.500  1.0
  Ni  Ni1  1  0.001  0.001  0.000  1.0
  P  P2  1  0.266  0.674  0.554  1.0
  P  P3  1  0.674  0.266  0.446  1.0
  O  O4  1  0.817  0.159  0.697  1.0
  O  O5  1  0.149  0.487  0.645  1.0
  O  O6  1  0.867  0.270  0.245  1.0
  O  O7  1  0.270  0.867  0.755  1.0
  O  O8  1  0.547  0.547  0.500  1.0
  O  O9  1  0.159  0.817  0.303  1.0
  O  O10  1  0.487  0.149  0.355  1.0
[/CIF]
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The structure described by MgNiP2O7 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. Ni(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(3) 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  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(1), and one P(1) atom. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Mg(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. is represented by the CIF card [CIF]
data_MgNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.802
_cell_length_b   5.802
_cell_length_c   5.185
_cell_angle_alpha   88.339
_cell_angle_beta   91.668
_cell_angle_gamma   73.379
_symmetry_Int_Tables_number   1
_cell_volume   167.064
_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
  Mg  Mg0  1  0.170  0.170  0.500  1.0
  Ni  Ni1  1  0.001  0.001  0.000  1.0
  P  P2  1  0.266  0.674  0.554  1.0
  P  P3  1  0.674  0.266  0.446  1.0
  O  O4  1  0.817  0.159  0.697  1.0
  O  O5  1  0.149  0.487  0.645  1.0
  O  O6  1  0.867  0.270  0.245  1.0
  O  O7  1  0.270  0.867  0.755  1.0
  O  O8  1  0.547  0.547  0.500  1.0
  O  O9  1  0.159  0.817  0.303  1.0
  O  O10  1  0.487  0.149  0.355  1.0
[/CIF]
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