The crystal structure described by MgGd2Cr2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form distorted MgO6 octahedra that share  a cornercorner with one Cr(1)O4 tetrahedra,  a cornercorner with one Cr(2)O4 tetrahedra,  an edgeedge with one Cr(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O4 tetrahedra. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(3), one O(6), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Cr site, Cr(2) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom to form distorted corner-sharing OGd2MgCr trigonal pyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Gd(1), one Gd(2), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Gd(1), one Gd(2), and one Cr(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom to form distorted corner-sharing OGd2MgCr trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2MgCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.102
_cell_length_b   6.255
_cell_length_c   6.242
_cell_angle_alpha   107.921
_cell_angle_beta   105.147
_cell_angle_gamma   117.173
_symmetry_Int_Tables_number   1
_cell_volume   177.503
_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
  Gd  Gd0  1  0.139  0.886  0.293  1.0
  Gd  Gd1  1  0.864  0.149  0.745  1.0
  Mg  Mg2  1  0.983  0.719  0.732  1.0
  Cr  Cr3  1  0.397  0.618  0.753  1.0
  Cr  Cr4  1  0.601  0.352  0.214  1.0
  O  O5  1  0.790  0.729  0.429  1.0
  O  O6  1  0.358  0.817  0.605  1.0
  O  O7  1  0.761  0.778  0.916  1.0
  O  O8  1  0.825  0.385  0.078  1.0
  O  O9  1  0.651  0.263  0.469  1.0
  O  O10  1  0.172  0.254  0.561  1.0
  O  O11  1  0.237  0.145  0.011  1.0
  O  O12  1  0.211  0.642  0.942  1.0
[/CIF]
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The crystal structure described by MgGd2Cr2O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form distorted MgO6 octahedra that share  a cornercorner with one Cr(1)O4 tetrahedra,  a cornercorner with one Cr(2)O4 tetrahedra,  an edgeedge with one Cr(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O4 tetrahedra. There are two inequivalent Gd sites. In the first Gd site, Gd(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Gd site, Gd(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(2), one O(3), one O(6), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Cr site, Cr(2) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom to form distorted corner-sharing OGd2MgCr trigonal pyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Gd(1), one Gd(2), and one Cr(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Gd(1), one Gd(2), and one Cr(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Mg(1), one Gd(1), one Gd(2), and one Cr(2) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Gd(1), one Gd(2), and one Cr(1) atom to form distorted corner-sharing OGd2MgCr trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Gd2MgCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.102
_cell_length_b   6.255
_cell_length_c   6.242
_cell_angle_alpha   107.921
_cell_angle_beta   105.147
_cell_angle_gamma   117.173
_symmetry_Int_Tables_number   1
_cell_volume   177.503
_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
  Gd  Gd0  1  0.139  0.886  0.293  1.0
  Gd  Gd1  1  0.864  0.149  0.745  1.0
  Mg  Mg2  1  0.983  0.719  0.732  1.0
  Cr  Cr3  1  0.397  0.618  0.753  1.0
  Cr  Cr4  1  0.601  0.352  0.214  1.0
  O  O5  1  0.790  0.729  0.429  1.0
  O  O6  1  0.358  0.817  0.605  1.0
  O  O7  1  0.761  0.778  0.916  1.0
  O  O8  1  0.825  0.385  0.078  1.0
  O  O9  1  0.651  0.263  0.469  1.0
  O  O10  1  0.172  0.254  0.561  1.0
  O  O11  1  0.237  0.145  0.011  1.0
  O  O12  1  0.211  0.642  0.942  1.0
[/CIF]
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