The material described by MnFe2(PO9)2 crystallizes in the triclinic P-1 space group. Mn(1) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. 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  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-53°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one O(9) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Mn(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Mn(1) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one O(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MnFe2(PO9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.340
_cell_length_b   7.034
_cell_length_c   9.816
_cell_angle_alpha   96.383
_cell_angle_beta   101.486
_cell_angle_gamma   109.561
_symmetry_Int_Tables_number   1
_cell_volume   334.078
_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
  Mn  Mn0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.500  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  P  P3  1  0.005  0.907  0.680  1.0
  P  P4  1  0.995  0.093  0.320  1.0
  O  O5  1  0.804  0.026  0.669  1.0
  O  O6  1  0.196  0.974  0.331  1.0
  O  O7  1  0.857  0.682  0.596  1.0
  O  O8  1  0.143  0.318  0.404  1.0
  O  O9  1  0.104  0.900  0.839  1.0
  O  O10  1  0.896  0.100  0.161  1.0
  O  O11  1  0.749  0.981  0.375  1.0
  O  O12  1  0.251  0.019  0.625  1.0
  O  O13  1  0.625  0.291  0.510  1.0
  O  O14  1  0.375  0.709  0.490  1.0
  O  O15  1  0.601  0.533  0.272  1.0
  O  O16  1  0.399  0.467  0.728  1.0
  O  O17  1  0.167  0.275  0.982  1.0
  O  O18  1  0.833  0.725  0.018  1.0
  O  O19  1  0.264  0.923  0.113  1.0
  O  O20  1  0.736  0.077  0.887  1.0
  O  O21  1  0.172  0.459  0.742  1.0
  O  O22  1  0.828  0.541  0.258  1.0
[/CIF]
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The material described by MnFe2(PO9)2 crystallizes in the triclinic P-1 space group. Mn(1) is bonded to two equivalent O(3), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra and corners with four equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. In the second Fe site, Fe(2) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 38°. 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  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-53°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(2) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Mn(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Fe(2) and one O(9) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Mn(1) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one Mn(1) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one O(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MnFe2(PO9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.340
_cell_length_b   7.034
_cell_length_c   9.816
_cell_angle_alpha   96.383
_cell_angle_beta   101.486
_cell_angle_gamma   109.561
_symmetry_Int_Tables_number   1
_cell_volume   334.078
_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
  Mn  Mn0  1  0.000  0.000  0.000  1.0
  Fe  Fe1  1  0.500  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  P  P3  1  0.005  0.907  0.680  1.0
  P  P4  1  0.995  0.093  0.320  1.0
  O  O5  1  0.804  0.026  0.669  1.0
  O  O6  1  0.196  0.974  0.331  1.0
  O  O7  1  0.857  0.682  0.596  1.0
  O  O8  1  0.143  0.318  0.404  1.0
  O  O9  1  0.104  0.900  0.839  1.0
  O  O10  1  0.896  0.100  0.161  1.0
  O  O11  1  0.749  0.981  0.375  1.0
  O  O12  1  0.251  0.019  0.625  1.0
  O  O13  1  0.625  0.291  0.510  1.0
  O  O14  1  0.375  0.709  0.490  1.0
  O  O15  1  0.601  0.533  0.272  1.0
  O  O16  1  0.399  0.467  0.728  1.0
  O  O17  1  0.167  0.275  0.982  1.0
  O  O18  1  0.833  0.725  0.018  1.0
  O  O19  1  0.264  0.923  0.113  1.0
  O  O20  1  0.736  0.077  0.887  1.0
  O  O21  1  0.172  0.459  0.742  1.0
  O  O22  1  0.828  0.541  0.258  1.0
[/CIF]
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