The material described by MgSm2Cr2O8 is Esseneite-like structured and crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cr(1)O4 tetrahedra. Sm(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) 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 54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Sm(1), and one Cr(1) atom. In the second O site, O(2) is bonded to one Mg(1), two equivalent Sm(1), and one Cr(1) atom to form distorted corner-sharing OSm2MgCr trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Sm(1) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Sm(1), and one Cr(1) atom. is represented by the CIF file [CIF]
data_Sm2MgCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.108
_cell_length_b   6.284
_cell_length_c   6.108
_cell_angle_alpha   105.121
_cell_angle_beta   105.302
_cell_angle_gamma   117.036
_symmetry_Int_Tables_number   1
_cell_volume   180.531
_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
  Sm  Sm0  1  0.349  0.599  0.712  1.0
  Sm  Sm1  1  0.613  0.401  0.250  1.0
  Mg  Mg2  1  0.768  0.000  0.268  1.0
  Cr  Cr3  1  0.882  0.138  0.780  1.0
  Cr  Cr4  1  0.142  0.862  0.245  1.0
  O  O5  1  0.238  0.205  0.387  1.0
  O  O6  1  0.858  0.301  0.569  1.0
  O  O7  1  0.242  0.306  0.916  1.0
  O  O8  1  0.353  0.868  0.091  1.0
  O  O9  1  0.110  0.694  0.436  1.0
  O  O10  1  0.682  0.795  0.533  1.0
  O  O11  1  0.768  0.699  0.057  1.0
  O  O12  1  0.723  0.132  0.985  1.0
[/CIF]
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The material described by MgSm2Cr2O8 is Esseneite-like structured and crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent Cr(1)O4 tetrahedra and edges with two equivalent Cr(1)O4 tetrahedra. Sm(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) 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 54°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Sm(1), and one Cr(1) atom. In the second O site, O(2) is bonded to one Mg(1), two equivalent Sm(1), and one Cr(1) atom to form distorted corner-sharing OSm2MgCr trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to two equivalent Sm(1) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Sm(1), and one Cr(1) atom. is represented by the CIF file [CIF]
data_Sm2MgCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.108
_cell_length_b   6.284
_cell_length_c   6.108
_cell_angle_alpha   105.121
_cell_angle_beta   105.302
_cell_angle_gamma   117.036
_symmetry_Int_Tables_number   1
_cell_volume   180.531
_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
  Sm  Sm0  1  0.349  0.599  0.712  1.0
  Sm  Sm1  1  0.613  0.401  0.250  1.0
  Mg  Mg2  1  0.768  0.000  0.268  1.0
  Cr  Cr3  1  0.882  0.138  0.780  1.0
  Cr  Cr4  1  0.142  0.862  0.245  1.0
  O  O5  1  0.238  0.205  0.387  1.0
  O  O6  1  0.858  0.301  0.569  1.0
  O  O7  1  0.242  0.306  0.916  1.0
  O  O8  1  0.353  0.868  0.091  1.0
  O  O9  1  0.110  0.694  0.436  1.0
  O  O10  1  0.682  0.795  0.533  1.0
  O  O11  1  0.768  0.699  0.057  1.0
  O  O12  1  0.723  0.132  0.985  1.0
[/CIF]
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