The compound described by MgMn2Fe2(PO4)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(1), one O(11), and two equivalent O(3) atoms to form MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 66-68°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. In the second Mn site, Mn(2) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(11), one O(7), two equivalent O(10), and two equivalent O(9) atoms to form distorted FeO6 octahedra that share corners with four equivalent Fe(2)O6 pentagonal pyramids,  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(12), one O(8), two equivalent O(10), and two equivalent O(9) atoms to form distorted FeO6 pentagonal pyramids that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 pentagonal pyramid, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 63°. In the second P site, P(2) is bonded to one O(5), one O(7), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-51°. In the third P site, P(3) is bonded to one O(6), one O(8), and two equivalent O(9) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 pentagonal pyramid, and  an edgeedge with one Fe(2)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 58°. In the fourth P site, P(4) is bonded to one O(1), one O(11), and two equivalent O(10) atoms to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 pentagonal pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one P(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(4) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2Fe2(PO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.222
_cell_length_b   5.987
_cell_length_c   5.068
_cell_angle_alpha   89.993
_cell_angle_beta   90.031
_cell_angle_gamma   90.005
_symmetry_Int_Tables_number   1
_cell_volume   310.214
_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  0.056  0.750  0.076  1.0
  Mn  Mn1  1  0.238  0.750  0.493  1.0
  Mn  Mn2  1  0.302  0.250  0.894  1.0
  Fe  Fe3  1  0.717  0.750  0.062  1.0
  Fe  Fe4  1  0.769  0.250  0.538  1.0
  P  P5  1  0.093  0.250  0.377  1.0
  P  P6  1  0.411  0.750  0.937  1.0
  P  P7  1  0.601  0.250  0.095  1.0
  P  P8  1  0.896  0.750  0.596  1.0
  O  O9  1  0.043  0.750  0.690  1.0
  O  O10  1  0.146  0.250  0.663  1.0
  O  O11  1  0.146  0.036  0.229  1.0
  O  O12  1  0.146  0.465  0.229  1.0
  O  O13  1  0.331  0.555  0.795  1.0
  O  O14  1  0.331  0.945  0.794  1.0
  O  O15  1  0.387  0.750  0.231  1.0
  O  O16  1  0.450  0.250  0.136  1.0
  O  O17  1  0.550  0.750  0.847  1.0
  O  O18  1  0.629  0.250  0.799  1.0
  O  O19  1  0.668  0.052  0.247  1.0
  O  O20  1  0.668  0.448  0.247  1.0
  O  O21  1  0.826  0.545  0.718  1.0
  O  O22  1  0.826  0.955  0.719  1.0
  O  O23  1  0.895  0.750  0.290  1.0
  O  O24  1  0.943  0.250  0.367  1.0
[/CIF]
.
The compound described by MgMn2Fe2(PO4)4 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(1), one O(11), and two equivalent O(3) atoms to form MgO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 66-68°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(5), two equivalent O(3), and two equivalent O(4) atoms to form distorted MnO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and  an edgeedge with one P(2)O4 tetrahedra. In the second Mn site, Mn(2) is bonded in a distorted rectangular see-saw-like geometry to one O(2), one O(6), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(11), one O(7), two equivalent O(10), and two equivalent O(9) atoms to form distorted FeO6 octahedra that share corners with four equivalent Fe(2)O6 pentagonal pyramids,  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and  an edgeedge with one P(4)O4 tetrahedra. In the second Fe site, Fe(2) is bonded to one O(12), one O(8), two equivalent O(10), and two equivalent O(9) atoms to form distorted FeO6 pentagonal pyramids that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(4)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-51°. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(12), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 pentagonal pyramid, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 63°. In the second P site, P(2) is bonded to one O(5), one O(7), and two equivalent O(4) atoms to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and  an edgeedge with one Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-51°. In the third P site, P(3) is bonded to one O(6), one O(8), and two equivalent O(9) atoms to form PO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one Fe(2)O6 pentagonal pyramid, and  an edgeedge with one Fe(2)O6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 58°. In the fourth P site, P(4) is bonded to one O(1), one O(11), and two equivalent O(10) atoms to form PO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 pentagonal pyramids, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-57°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one P(4) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mn(2) and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mn(1), one Mn(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Mn(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mn(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(3) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one P(3) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one P(4) atom. In the eleventh O site, O(11) is bonded in a trigonal planar geometry to one Mg(1), one Fe(1), and one P(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn2Fe2(PO4)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.222
_cell_length_b   5.987
_cell_length_c   5.068
_cell_angle_alpha   89.993
_cell_angle_beta   90.031
_cell_angle_gamma   90.005
_symmetry_Int_Tables_number   1
_cell_volume   310.214
_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  0.056  0.750  0.076  1.0
  Mn  Mn1  1  0.238  0.750  0.493  1.0
  Mn  Mn2  1  0.302  0.250  0.894  1.0
  Fe  Fe3  1  0.717  0.750  0.062  1.0
  Fe  Fe4  1  0.769  0.250  0.538  1.0
  P  P5  1  0.093  0.250  0.377  1.0
  P  P6  1  0.411  0.750  0.937  1.0
  P  P7  1  0.601  0.250  0.095  1.0
  P  P8  1  0.896  0.750  0.596  1.0
  O  O9  1  0.043  0.750  0.690  1.0
  O  O10  1  0.146  0.250  0.663  1.0
  O  O11  1  0.146  0.036  0.229  1.0
  O  O12  1  0.146  0.465  0.229  1.0
  O  O13  1  0.331  0.555  0.795  1.0
  O  O14  1  0.331  0.945  0.794  1.0
  O  O15  1  0.387  0.750  0.231  1.0
  O  O16  1  0.450  0.250  0.136  1.0
  O  O17  1  0.550  0.750  0.847  1.0
  O  O18  1  0.629  0.250  0.799  1.0
  O  O19  1  0.668  0.052  0.247  1.0
  O  O20  1  0.668  0.448  0.247  1.0
  O  O21  1  0.826  0.545  0.718  1.0
  O  O22  1  0.826  0.955  0.719  1.0
  O  O23  1  0.895  0.750  0.290  1.0
  O  O24  1  0.943  0.250  0.367  1.0
[/CIF]
.