The crystal structure described by MgFeP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O5 trigonal bipyramids. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-50°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Mg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-53°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), 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(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 Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one P(2) atom. is represented by the CIF file [CIF]
data_MgFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.583
_cell_length_b   6.438
_cell_length_c   7.417
_cell_angle_alpha   82.305
_cell_angle_beta   86.719
_cell_angle_gamma   72.012
_symmetry_Int_Tables_number   1
_cell_volume   251.220
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.258  0.158  0.200  1.0
  Fe  Fe1  1  0.742  0.842  0.800  1.0
  Mg  Mg2  1  0.331  0.657  0.652  1.0
  Mg  Mg3  1  0.669  0.343  0.348  1.0
  O  O4  1  0.112  0.688  0.897  1.0
  O  O5  1  0.888  0.312  0.103  1.0
  O  O6  1  0.301  0.864  0.118  1.0
  O  O7  1  0.699  0.136  0.882  1.0
  O  O8  1  0.356  0.452  0.171  1.0
  O  O9  1  0.644  0.548  0.829  1.0
  O  O10  1  0.611  0.648  0.431  1.0
  O  O11  1  0.389  0.352  0.569  1.0
  O  O12  1  0.043  0.221  0.458  1.0
  O  O13  1  0.957  0.779  0.542  1.0
  O  O14  1  0.072  0.282  0.793  1.0
  O  O15  1  0.928  0.718  0.207  1.0
  O  O16  1  0.623  0.041  0.330  1.0
  O  O17  1  0.377  0.959  0.670  1.0
  P  P18  1  0.190  0.683  0.094  1.0
  P  P19  1  0.810  0.317  0.906  1.0
  P  P20  1  0.224  0.199  0.613  1.0
  P  P21  1  0.776  0.801  0.387  1.0
[/CIF]
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The crystal structure described by MgFeP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(1), one O(3), one O(5), one O(7), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O5 trigonal bipyramids. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(7) atom to form FeO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 47-50°. In the second P site, P(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with four equivalent Mg(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 30-53°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), 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(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 Fe(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one P(2) atom. is represented by the CIF file [CIF]
data_MgFeP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.583
_cell_length_b   6.438
_cell_length_c   7.417
_cell_angle_alpha   82.305
_cell_angle_beta   86.719
_cell_angle_gamma   72.012
_symmetry_Int_Tables_number   1
_cell_volume   251.220
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.258  0.158  0.200  1.0
  Fe  Fe1  1  0.742  0.842  0.800  1.0
  Mg  Mg2  1  0.331  0.657  0.652  1.0
  Mg  Mg3  1  0.669  0.343  0.348  1.0
  O  O4  1  0.112  0.688  0.897  1.0
  O  O5  1  0.888  0.312  0.103  1.0
  O  O6  1  0.301  0.864  0.118  1.0
  O  O7  1  0.699  0.136  0.882  1.0
  O  O8  1  0.356  0.452  0.171  1.0
  O  O9  1  0.644  0.548  0.829  1.0
  O  O10  1  0.611  0.648  0.431  1.0
  O  O11  1  0.389  0.352  0.569  1.0
  O  O12  1  0.043  0.221  0.458  1.0
  O  O13  1  0.957  0.779  0.542  1.0
  O  O14  1  0.072  0.282  0.793  1.0
  O  O15  1  0.928  0.718  0.207  1.0
  O  O16  1  0.623  0.041  0.330  1.0
  O  O17  1  0.377  0.959  0.670  1.0
  P  P18  1  0.190  0.683  0.094  1.0
  P  P19  1  0.810  0.317  0.906  1.0
  P  P20  1  0.224  0.199  0.613  1.0
  P  P21  1  0.776  0.801  0.387  1.0
[/CIF]
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