The material structure described by MgFe3PO7 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, corners with two equivalent Fe(3)O5 trigonal bipyramids,  an edgeedge with one Fe(2)O5 trigonal bipyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(3)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the third Fe site, Fe(3) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. P(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids, and corners with two equivalent Fe(3)O5 trigonal bipyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one P(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. is represented by the CIF file [CIF]
data_MgFe3PO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.490
_cell_length_b   5.396
_cell_length_c   5.491
_cell_angle_alpha   99.183
_cell_angle_beta   104.822
_cell_angle_gamma   99.116
_symmetry_Int_Tables_number   1
_cell_volume   151.807
_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  0.697  0.674  0.698  1.0
  Fe  Fe1  1  0.506  0.539  0.132  1.0
  Fe  Fe2  1  0.131  0.542  0.505  1.0
  Fe  Fe3  1  0.535  0.151  0.536  1.0
  P  P4  1  0.018  0.011  0.017  1.0
  O  O5  1  0.126  0.830  0.840  1.0
  O  O6  1  0.842  0.829  0.124  1.0
  O  O7  1  0.834  0.140  0.834  1.0
  O  O8  1  0.752  0.409  0.427  1.0
  O  O9  1  0.228  0.219  0.227  1.0
  O  O10  1  0.425  0.409  0.752  1.0
  O  O11  1  0.432  0.784  0.432  1.0
[/CIF]
.
The material structure described by MgFe3PO7 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(2)O5 trigonal bipyramids, corners with two equivalent Fe(3)O5 trigonal bipyramids,  an edgeedge with one Fe(2)O5 trigonal bipyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(3)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(3)O5 trigonal bipyramid. In the third Fe site, Fe(3) is bonded to one O(3), one O(4), one O(5), one O(6), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids,  an edgeedge with one Fe(1)O5 trigonal bipyramid, and  an edgeedge with one Fe(2)O5 trigonal bipyramid. P(1) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form PO4 tetrahedra that share corners with two equivalent Fe(1)O5 trigonal bipyramids, corners with two equivalent Fe(2)O5 trigonal bipyramids, and corners with two equivalent Fe(3)O5 trigonal bipyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one P(1) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(3), and one P(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one P(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. is represented by the CIF file [CIF]
data_MgFe3PO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.490
_cell_length_b   5.396
_cell_length_c   5.491
_cell_angle_alpha   99.183
_cell_angle_beta   104.822
_cell_angle_gamma   99.116
_symmetry_Int_Tables_number   1
_cell_volume   151.807
_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  0.697  0.674  0.698  1.0
  Fe  Fe1  1  0.506  0.539  0.132  1.0
  Fe  Fe2  1  0.131  0.542  0.505  1.0
  Fe  Fe3  1  0.535  0.151  0.536  1.0
  P  P4  1  0.018  0.011  0.017  1.0
  O  O5  1  0.126  0.830  0.840  1.0
  O  O6  1  0.842  0.829  0.124  1.0
  O  O7  1  0.834  0.140  0.834  1.0
  O  O8  1  0.752  0.409  0.427  1.0
  O  O9  1  0.228  0.219  0.227  1.0
  O  O10  1  0.425  0.409  0.752  1.0
  O  O11  1  0.432  0.784  0.432  1.0
[/CIF]
.