The structure described by MgCrP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(2), one O(3), one O(7), and two equivalent O(5) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Cr(1)O5 square pyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. Cr(1) is bonded to one O(2), one O(4), one O(7), and two equivalent O(6) atoms to form CrO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Cr(1)O5 square pyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O5 square pyramids,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one P(1) 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(2) atom. is represented by the CIF file [CIF]
data_MgCrP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.372
_cell_length_b   6.430
_cell_length_c   7.294
_cell_angle_alpha   70.125
_cell_angle_beta   74.907
_cell_angle_gamma   81.443
_symmetry_Int_Tables_number   1
_cell_volume   270.784
_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
  Mg  Mg0  1  0.926  0.288  0.187  1.0
  Mg  Mg1  1  0.074  0.712  0.813  1.0
  Cr  Cr2  1  0.686  0.093  0.780  1.0
  Cr  Cr3  1  0.313  0.907  0.220  1.0
  P  P4  1  0.175  0.213  0.765  1.0
  P  P5  1  0.825  0.787  0.235  1.0
  P  P6  1  0.621  0.638  0.682  1.0
  P  P7  1  0.379  0.362  0.318  1.0
  O  O8  1  0.746  0.625  0.457  1.0
  O  O9  1  0.255  0.375  0.543  1.0
  O  O10  1  0.017  0.055  0.760  1.0
  O  O11  1  0.983  0.945  0.240  1.0
  O  O12  1  0.610  0.265  0.330  1.0
  O  O13  1  0.391  0.735  0.670  1.0
  O  O14  1  0.359  0.601  0.188  1.0
  O  O15  1  0.641  0.399  0.812  1.0
  O  O16  1  0.937  0.628  0.117  1.0
  O  O17  1  0.063  0.373  0.883  1.0
  O  O18  1  0.637  0.927  0.151  1.0
  O  O19  1  0.362  0.073  0.850  1.0
  O  O20  1  0.237  0.214  0.275  1.0
  O  O21  1  0.763  0.786  0.725  1.0
[/CIF]
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The structure described by MgCrP2O7 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to one O(2), one O(3), one O(7), and two equivalent O(5) atoms to form MgO5 trigonal bipyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Cr(1)O5 square pyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. Cr(1) is bonded to one O(2), one O(4), one O(7), and two equivalent O(6) atoms to form CrO5 square pyramids that share corners with two equivalent P(2)O4 tetrahedra, corners with three equivalent P(1)O4 tetrahedra,  an edgeedge with one Cr(1)O5 square pyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Cr(1)O5 square pyramids,  a cornercorner with one P(2)O4 tetrahedra, and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(1), one O(3), one O(4), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Cr(1)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra, and corners with two equivalent Mg(1)O5 trigonal bipyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Cr(1) and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one P(1) 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(2) atom. is represented by the CIF file [CIF]
data_MgCrP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.372
_cell_length_b   6.430
_cell_length_c   7.294
_cell_angle_alpha   70.125
_cell_angle_beta   74.907
_cell_angle_gamma   81.443
_symmetry_Int_Tables_number   1
_cell_volume   270.784
_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
  Mg  Mg0  1  0.926  0.288  0.187  1.0
  Mg  Mg1  1  0.074  0.712  0.813  1.0
  Cr  Cr2  1  0.686  0.093  0.780  1.0
  Cr  Cr3  1  0.313  0.907  0.220  1.0
  P  P4  1  0.175  0.213  0.765  1.0
  P  P5  1  0.825  0.787  0.235  1.0
  P  P6  1  0.621  0.638  0.682  1.0
  P  P7  1  0.379  0.362  0.318  1.0
  O  O8  1  0.746  0.625  0.457  1.0
  O  O9  1  0.255  0.375  0.543  1.0
  O  O10  1  0.017  0.055  0.760  1.0
  O  O11  1  0.983  0.945  0.240  1.0
  O  O12  1  0.610  0.265  0.330  1.0
  O  O13  1  0.391  0.735  0.670  1.0
  O  O14  1  0.359  0.601  0.188  1.0
  O  O15  1  0.641  0.399  0.812  1.0
  O  O16  1  0.937  0.628  0.117  1.0
  O  O17  1  0.063  0.373  0.883  1.0
  O  O18  1  0.637  0.927  0.151  1.0
  O  O19  1  0.362  0.073  0.850  1.0
  O  O20  1  0.237  0.214  0.275  1.0
  O  O21  1  0.763  0.786  0.725  1.0
[/CIF]
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