The material described by Mn2P2O7 crystallizes in the monoclinic P2_1/c space group. Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Mn(1)O6 octahedra. 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 six equivalent Mn(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom. is represented by the CIF card [CIF]
data_Mn2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.543
_cell_length_b   10.267
_cell_length_c   5.380
_cell_angle_alpha   90.000
_cell_angle_beta   97.076
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   249.023
_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
  Mn  Mn0  1  0.101  0.654  0.409  1.0
  Mn  Mn1  1  0.899  0.154  0.091  1.0
  Mn  Mn2  1  0.101  0.846  0.909  1.0
  Mn  Mn3  1  0.899  0.346  0.591  1.0
  P  P4  1  0.359  0.110  0.651  1.0
  P  P5  1  0.359  0.390  0.151  1.0
  P  P6  1  0.641  0.610  0.849  1.0
  P  P7  1  0.641  0.890  0.349  1.0
  O  O8  1  0.500  1.000  0.500  1.0
  O  O9  1  0.500  0.500  0.000  1.0
  O  O10  1  0.130  0.322  0.965  1.0
  O  O11  1  0.130  0.178  0.465  1.0
  O  O12  1  0.870  0.822  0.535  1.0
  O  O13  1  0.870  0.678  0.035  1.0
  O  O14  1  0.212  0.044  0.857  1.0
  O  O15  1  0.212  0.456  0.357  1.0
  O  O16  1  0.788  0.544  0.643  1.0
  O  O17  1  0.788  0.956  0.143  1.0
  O  O18  1  0.387  0.698  0.745  1.0
  O  O19  1  0.387  0.802  0.245  1.0
  O  O20  1  0.613  0.198  0.755  1.0
  O  O21  1  0.613  0.302  0.255  1.0
[/CIF]
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The material described by Mn2P2O7 crystallizes in the monoclinic P2_1/c space group. Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Mn(1)O6 octahedra. 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 six equivalent Mn(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-62°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(1) atom. is represented by the CIF card [CIF]
data_Mn2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.543
_cell_length_b   10.267
_cell_length_c   5.380
_cell_angle_alpha   90.000
_cell_angle_beta   97.076
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   249.023
_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
  Mn  Mn0  1  0.101  0.654  0.409  1.0
  Mn  Mn1  1  0.899  0.154  0.091  1.0
  Mn  Mn2  1  0.101  0.846  0.909  1.0
  Mn  Mn3  1  0.899  0.346  0.591  1.0
  P  P4  1  0.359  0.110  0.651  1.0
  P  P5  1  0.359  0.390  0.151  1.0
  P  P6  1  0.641  0.610  0.849  1.0
  P  P7  1  0.641  0.890  0.349  1.0
  O  O8  1  0.500  1.000  0.500  1.0
  O  O9  1  0.500  0.500  0.000  1.0
  O  O10  1  0.130  0.322  0.965  1.0
  O  O11  1  0.130  0.178  0.465  1.0
  O  O12  1  0.870  0.822  0.535  1.0
  O  O13  1  0.870  0.678  0.035  1.0
  O  O14  1  0.212  0.044  0.857  1.0
  O  O15  1  0.212  0.456  0.357  1.0
  O  O16  1  0.788  0.544  0.643  1.0
  O  O17  1  0.788  0.956  0.143  1.0
  O  O18  1  0.387  0.698  0.745  1.0
  O  O19  1  0.387  0.802  0.245  1.0
  O  O20  1  0.613  0.198  0.755  1.0
  O  O21  1  0.613  0.302  0.255  1.0
[/CIF]
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