The structure described by MgMn2(PO4)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(1), one O(6), and two equivalent O(2) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 73-77°. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with two equivalent Mn(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-53°. In the second P site, P(2) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-51°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMgMn2P tetrahedra. 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(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one 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(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(2) atom. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMgMn2P tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.051
_cell_length_b   5.066
_cell_length_c   6.465
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   67.241
_symmetry_Int_Tables_number   1
_cell_volume   152.526
_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  0.677  0.669  0.250  1.0
  Mn  Mn1  1  0.009  0.008  0.516  1.0
  Mn  Mn2  1  0.009  0.008  0.984  1.0
  P  P3  1  0.350  0.350  0.250  1.0
  P  P4  1  0.644  0.643  0.750  1.0
  O  O5  1  0.693  0.249  0.250  1.0
  O  O6  1  0.748  0.748  0.549  1.0
  O  O7  1  0.249  0.251  0.055  1.0
  O  O8  1  0.249  0.251  0.445  1.0
  O  O9  1  0.768  0.312  0.750  1.0
  O  O10  1  0.311  0.767  0.750  1.0
  O  O11  1  0.748  0.748  0.951  1.0
  O  O12  1  0.251  0.692  0.250  1.0
[/CIF]
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The structure described by MgMn2(PO4)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(1), one O(6), and two equivalent O(2) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 73-77°. Mn(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form MnO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and edges with two equivalent Mn(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(6), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and  an edgeedge with one Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 43-53°. In the second P site, P(2) is bonded to one O(4), one O(5), and two equivalent O(2) atoms to form PO4 tetrahedra that share corners with six equivalent Mn(1)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-51°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMgMn2P tetrahedra. 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(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one 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(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to two equivalent Mn(1) and one P(2) atom. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Mn(1), and one P(1) atom to form distorted edge-sharing OMgMn2P tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.051
_cell_length_b   5.066
_cell_length_c   6.465
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   67.241
_symmetry_Int_Tables_number   1
_cell_volume   152.526
_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  0.677  0.669  0.250  1.0
  Mn  Mn1  1  0.009  0.008  0.516  1.0
  Mn  Mn2  1  0.009  0.008  0.984  1.0
  P  P3  1  0.350  0.350  0.250  1.0
  P  P4  1  0.644  0.643  0.750  1.0
  O  O5  1  0.693  0.249  0.250  1.0
  O  O6  1  0.748  0.748  0.549  1.0
  O  O7  1  0.249  0.251  0.055  1.0
  O  O8  1  0.249  0.251  0.445  1.0
  O  O9  1  0.768  0.312  0.750  1.0
  O  O10  1  0.311  0.767  0.750  1.0
  O  O11  1  0.748  0.748  0.951  1.0
  O  O12  1  0.251  0.692  0.250  1.0
[/CIF]
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