The material described by Mg2P2O7 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form distorted MgO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Mg(1)O6 octahedra. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share corners with six equivalent Mg(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-61°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent P(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Mg2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.498
_cell_length_b   5.244
_cell_length_c   5.244
_cell_angle_alpha   104.227
_cell_angle_beta   98.260
_cell_angle_gamma   98.260
_symmetry_Int_Tables_number   1
_cell_volume   116.558
_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  0.500  0.688  0.312  1.0
  Mg  Mg1  1  0.500  0.312  0.688  1.0
  P  P2  1  0.093  0.780  0.780  1.0
  P  P3  1  0.907  0.220  0.220  1.0
  O  O4  1  0.280  0.926  0.621  1.0
  O  O5  1  0.720  0.379  0.074  1.0
  O  O6  1  0.720  0.074  0.379  1.0
  O  O7  1  0.280  0.621  0.926  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.787  0.619  0.619  1.0
  O  O10  1  0.213  0.381  0.381  1.0
[/CIF]
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The material described by Mg2P2O7 crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form distorted MgO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Mg(1)O6 octahedra. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share corners with six equivalent Mg(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-61°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent P(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Mg2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.498
_cell_length_b   5.244
_cell_length_c   5.244
_cell_angle_alpha   104.227
_cell_angle_beta   98.260
_cell_angle_gamma   98.260
_symmetry_Int_Tables_number   1
_cell_volume   116.558
_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  0.500  0.688  0.312  1.0
  Mg  Mg1  1  0.500  0.312  0.688  1.0
  P  P2  1  0.093  0.780  0.780  1.0
  P  P3  1  0.907  0.220  0.220  1.0
  O  O4  1  0.280  0.926  0.621  1.0
  O  O5  1  0.720  0.379  0.074  1.0
  O  O6  1  0.720  0.074  0.379  1.0
  O  O7  1  0.280  0.621  0.926  1.0
  O  O8  1  0.000  0.000  0.000  1.0
  O  O9  1  0.787  0.619  0.619  1.0
  O  O10  1  0.213  0.381  0.381  1.0
[/CIF]
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