The compound described by MgMn2(PO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form MgO6 octahedra that share corners with three equivalent Mn(1)O5 square pyramids, corners with three equivalent Mn(2)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted MnO5 square pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 59-62°. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form distorted MnO5 square pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 59-62°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with three equivalent Mn(1)O5 square pyramids, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with three equivalent Mn(2)O5 square pyramids, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate 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(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), 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 trigonal planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.588
_cell_length_b   4.827
_cell_length_c   6.427
_cell_angle_alpha   95.910
_cell_angle_beta   90.887
_cell_angle_gamma   71.009
_symmetry_Int_Tables_number   1
_cell_volume   163.039
_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  0.481  0.516  0.003  1.0
  Mn  Mn1  1  0.888  0.784  0.704  1.0
  Mn  Mn2  1  0.077  0.245  0.300  1.0
  P  P3  1  0.270  0.136  0.790  1.0
  P  P4  1  0.696  0.892  0.213  1.0
  O  O5  1  0.713  0.205  0.198  1.0
  O  O6  1  0.534  0.146  0.726  1.0
  O  O7  1  0.216  0.318  0.009  1.0
  O  O8  1  0.061  0.292  0.636  1.0
  O  O9  1  0.750  0.710  0.994  1.0
  O  O10  1  0.252  0.824  0.805  1.0
  O  O11  1  0.905  0.737  0.367  1.0
  O  O12  1  0.432  0.882  0.276  1.0
[/CIF]
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The compound described by MgMn2(PO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form MgO6 octahedra that share corners with three equivalent Mn(1)O5 square pyramids, corners with three equivalent Mn(2)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  an edgeedge with one P(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form distorted MnO5 square pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and  an edgeedge with one Mn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 59-62°. In the second Mn site, Mn(2) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form distorted MnO5 square pyramids that share corners with three equivalent Mg(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  an edgeedge with one Mn(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 59-62°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mn(2)O5 square pyramids, corners with three equivalent Mn(1)O5 square pyramids, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, corners with three equivalent Mn(2)O5 square pyramids, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Mg(1), one Mn(2), and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate 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(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), 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 trigonal planar geometry to one Mg(1), one Mn(1), and one P(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), and one P(2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.588
_cell_length_b   4.827
_cell_length_c   6.427
_cell_angle_alpha   95.910
_cell_angle_beta   90.887
_cell_angle_gamma   71.009
_symmetry_Int_Tables_number   1
_cell_volume   163.039
_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  0.481  0.516  0.003  1.0
  Mn  Mn1  1  0.888  0.784  0.704  1.0
  Mn  Mn2  1  0.077  0.245  0.300  1.0
  P  P3  1  0.270  0.136  0.790  1.0
  P  P4  1  0.696  0.892  0.213  1.0
  O  O5  1  0.713  0.205  0.198  1.0
  O  O6  1  0.534  0.146  0.726  1.0
  O  O7  1  0.216  0.318  0.009  1.0
  O  O8  1  0.061  0.292  0.636  1.0
  O  O9  1  0.750  0.710  0.994  1.0
  O  O10  1  0.252  0.824  0.805  1.0
  O  O11  1  0.905  0.737  0.367  1.0
  O  O12  1  0.432  0.882  0.276  1.0
[/CIF]
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