The material described by MgMnP2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with three equivalent Mn(1)O6 pentagonal pyramids. Mn(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with three equivalent Mg(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(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 pentagonal pyramids, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-54°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 pentagonal pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-55°. 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 planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMnP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.388
_cell_length_b   5.394
_cell_length_c   4.573
_cell_angle_alpha   82.054
_cell_angle_beta   97.862
_cell_angle_gamma   75.793
_symmetry_Int_Tables_number   1
_cell_volume   125.558
_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  0.768  0.775  0.009  1.0
  Mn  Mn1  1  0.148  0.155  0.008  1.0
  P  P2  1  0.233  0.670  0.601  1.0
  P  P3  1  0.664  0.240  0.417  1.0
  O  O4  1  0.411  0.416  0.512  1.0
  O  O5  1  0.061  0.555  0.794  1.0
  O  O6  1  0.081  0.833  0.298  1.0
  O  O7  1  0.400  0.812  0.774  1.0
  O  O8  1  0.828  0.086  0.718  1.0
  O  O9  1  0.804  0.408  0.244  1.0
  O  O10  1  0.548  0.070  0.224  1.0
[/CIF]
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The material described by MgMnP2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with three equivalent Mn(1)O6 pentagonal pyramids. Mn(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form distorted MnO6 pentagonal pyramids that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with three equivalent Mg(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(3), and one O(4) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 pentagonal pyramids, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-54°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O6 pentagonal pyramids, and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-55°. 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 planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMnP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.388
_cell_length_b   5.394
_cell_length_c   4.573
_cell_angle_alpha   82.054
_cell_angle_beta   97.862
_cell_angle_gamma   75.793
_symmetry_Int_Tables_number   1
_cell_volume   125.558
_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  0.768  0.775  0.009  1.0
  Mn  Mn1  1  0.148  0.155  0.008  1.0
  P  P2  1  0.233  0.670  0.601  1.0
  P  P3  1  0.664  0.240  0.417  1.0
  O  O4  1  0.411  0.416  0.512  1.0
  O  O5  1  0.061  0.555  0.794  1.0
  O  O6  1  0.081  0.833  0.298  1.0
  O  O7  1  0.400  0.812  0.774  1.0
  O  O8  1  0.828  0.086  0.718  1.0
  O  O9  1  0.804  0.408  0.244  1.0
  O  O10  1  0.548  0.070  0.224  1.0
[/CIF]
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