The crystal structure described by MgCrP2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. Cr(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 two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-54°. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 30-54°. 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 Cr(1), and one P(2) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Cr(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 Cr(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. is represented by the CIF file [CIF]
data_MgCrP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.383
_cell_length_b   5.397
_cell_length_c   4.583
_cell_angle_alpha   80.715
_cell_angle_beta   99.126
_cell_angle_gamma   77.073
_symmetry_Int_Tables_number   1
_cell_volume   125.434
_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  0.770  0.779  0.010  1.0
  Cr  Cr1  1  0.145  0.160  0.014  1.0
  P  P2  1  0.656  0.247  0.418  1.0
  P  P3  1  0.241  0.663  0.598  1.0
  O  O4  1  0.069  0.552  0.797  1.0
  O  O5  1  0.792  0.424  0.251  1.0
  O  O6  1  0.828  0.093  0.724  1.0
  O  O7  1  0.422  0.796  0.764  1.0
  O  O8  1  0.397  0.407  0.505  1.0
  O  O9  1  0.084  0.837  0.295  1.0
  O  O10  1  0.543  0.075  0.222  1.0
[/CIF]
.
The crystal structure described by MgCrP2O7 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. Cr(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 two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 32-54°. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 30-54°. 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 Cr(1), and one P(2) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Cr(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 Cr(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Mg(1), one Cr(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. is represented by the CIF file [CIF]
data_MgCrP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.383
_cell_length_b   5.397
_cell_length_c   4.583
_cell_angle_alpha   80.715
_cell_angle_beta   99.126
_cell_angle_gamma   77.073
_symmetry_Int_Tables_number   1
_cell_volume   125.434
_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  0.770  0.779  0.010  1.0
  Cr  Cr1  1  0.145  0.160  0.014  1.0
  P  P2  1  0.656  0.247  0.418  1.0
  P  P3  1  0.241  0.663  0.598  1.0
  O  O4  1  0.069  0.552  0.797  1.0
  O  O5  1  0.792  0.424  0.251  1.0
  O  O6  1  0.828  0.093  0.724  1.0
  O  O7  1  0.422  0.796  0.764  1.0
  O  O8  1  0.397  0.407  0.505  1.0
  O  O9  1  0.084  0.837  0.295  1.0
  O  O10  1  0.543  0.075  0.222  1.0
[/CIF]
.