The structure described by Sm2FeSbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms to form distorted SmO8 hexagonal bipyramids that share edges with two equivalent Sm(1)O8 hexagonal bipyramids, edges with two equivalent Fe(1)O6 octahedra, and edges with four equivalent Sb(1)O6 octahedra. In the second Sm site, Sm(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms. Fe(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, and edges with two equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 50-52°. Sb(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 47-50°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sm(2) and two equivalent Fe(1) atoms to form distorted OSm2Fe2 tetrahedra that share corners with two equivalent O(4)Sm4 tetrahedra, corners with four equivalent O(1)Sm2Fe2 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. In the second O site, O(2) is bonded to two equivalent Sm(1) and two equivalent Sb(1) atoms to form distorted OSm2Sb2 tetrahedra that share corners with two equivalent O(4)Sm4 tetrahedra, corners with four equivalent O(2)Sm2Sb2 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Sm(2), one Fe(1), and one Sb(1) atom to form distorted OSm2FeSb tetrahedra that share corners with two equivalent O(1)Sm2Fe2 tetrahedra, corners with two equivalent O(2)Sm2Sb2 tetrahedra, corners with two equivalent O(4)Sm4 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(1)Sm2Fe2 tetrahedra,  an edgeedge with one O(2)Sm2Sb2 tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with two equivalent O(3)Sm2FeSb tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Sm(1) and two equivalent Sm(2) atoms to form OSm4 tetrahedra that share corners with two equivalent O(1)Sm2Fe2 tetrahedra, corners with two equivalent O(2)Sm2Sb2 tetrahedra, corners with four equivalent O(4)Sm4 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(1)Sm2Fe2 tetrahedra,  an edgeedge with one O(2)Sm2Sb2 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. is represented by the CIF file [CIF]
data_Sm2FeSbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.410
_cell_length_b   7.410
_cell_length_c   7.410
_cell_angle_alpha   120.393
_cell_angle_beta   119.367
_cell_angle_gamma   90.211
_symmetry_Int_Tables_number   1
_cell_volume   288.242
_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
  Sm  Sm0  1  0.500  0.000  0.000  1.0
  Sm  Sm1  1  0.500  0.500  0.500  1.0
  Sm  Sm2  1  0.500  0.000  0.500  1.0
  Sm  Sm3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.000  0.500  1.0
  Sb  Sb6  1  0.000  0.500  0.500  1.0
  Sb  Sb7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.914  0.164  0.750  1.0
  O  O9  1  0.328  0.578  0.750  1.0
  O  O10  1  0.914  0.576  0.740  1.0
  O  O11  1  0.336  0.173  0.760  1.0
  O  O12  1  0.914  0.173  0.337  1.0
  O  O13  1  0.336  0.576  0.163  1.0
  O  O14  1  0.086  0.836  0.250  1.0
  O  O15  1  0.672  0.422  0.250  1.0
  O  O16  1  0.086  0.424  0.260  1.0
  O  O17  1  0.664  0.827  0.240  1.0
  O  O18  1  0.086  0.827  0.663  1.0
  O  O19  1  0.664  0.424  0.837  1.0
  O  O20  1  0.623  0.873  0.750  1.0
  O  O21  1  0.377  0.127  0.250  1.0
[/CIF]
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The structure described by Sm2FeSbO7 crystallizes in the orthorhombic Imma space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent O(2), two equivalent O(4), and four equivalent O(3) atoms to form distorted SmO8 hexagonal bipyramids that share edges with two equivalent Sm(1)O8 hexagonal bipyramids, edges with two equivalent Fe(1)O6 octahedra, and edges with four equivalent Sb(1)O6 octahedra. In the second Sm site, Sm(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(1), two equivalent O(4), and four equivalent O(3) atoms. Fe(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Sb(1)O6 octahedra, and edges with two equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 50-52°. Sb(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form SbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Sm(1)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 47-50°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sm(2) and two equivalent Fe(1) atoms to form distorted OSm2Fe2 tetrahedra that share corners with two equivalent O(4)Sm4 tetrahedra, corners with four equivalent O(1)Sm2Fe2 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. In the second O site, O(2) is bonded to two equivalent Sm(1) and two equivalent Sb(1) atoms to form distorted OSm2Sb2 tetrahedra that share corners with two equivalent O(4)Sm4 tetrahedra, corners with four equivalent O(2)Sm2Sb2 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. In the third O site, O(3) is bonded to one Sm(1), one Sm(2), one Fe(1), and one Sb(1) atom to form distorted OSm2FeSb tetrahedra that share corners with two equivalent O(1)Sm2Fe2 tetrahedra, corners with two equivalent O(2)Sm2Sb2 tetrahedra, corners with two equivalent O(4)Sm4 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(1)Sm2Fe2 tetrahedra,  an edgeedge with one O(2)Sm2Sb2 tetrahedra,  an edgeedge with one O(4)Sm4 tetrahedra, and edges with two equivalent O(3)Sm2FeSb tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Sm(1) and two equivalent Sm(2) atoms to form OSm4 tetrahedra that share corners with two equivalent O(1)Sm2Fe2 tetrahedra, corners with two equivalent O(2)Sm2Sb2 tetrahedra, corners with four equivalent O(4)Sm4 tetrahedra, corners with eight equivalent O(3)Sm2FeSb tetrahedra,  an edgeedge with one O(1)Sm2Fe2 tetrahedra,  an edgeedge with one O(2)Sm2Sb2 tetrahedra, and edges with four equivalent O(3)Sm2FeSb tetrahedra. is represented by the CIF file [CIF]
data_Sm2FeSbO7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.410
_cell_length_b   7.410
_cell_length_c   7.410
_cell_angle_alpha   120.393
_cell_angle_beta   119.367
_cell_angle_gamma   90.211
_symmetry_Int_Tables_number   1
_cell_volume   288.242
_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
  Sm  Sm0  1  0.500  0.000  0.000  1.0
  Sm  Sm1  1  0.500  0.500  0.500  1.0
  Sm  Sm2  1  0.500  0.000  0.500  1.0
  Sm  Sm3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.000  0.500  0.000  1.0
  Fe  Fe5  1  0.000  0.000  0.500  1.0
  Sb  Sb6  1  0.000  0.500  0.500  1.0
  Sb  Sb7  1  0.500  0.500  0.000  1.0
  O  O8  1  0.914  0.164  0.750  1.0
  O  O9  1  0.328  0.578  0.750  1.0
  O  O10  1  0.914  0.576  0.740  1.0
  O  O11  1  0.336  0.173  0.760  1.0
  O  O12  1  0.914  0.173  0.337  1.0
  O  O13  1  0.336  0.576  0.163  1.0
  O  O14  1  0.086  0.836  0.250  1.0
  O  O15  1  0.672  0.422  0.250  1.0
  O  O16  1  0.086  0.424  0.260  1.0
  O  O17  1  0.664  0.827  0.240  1.0
  O  O18  1  0.086  0.827  0.663  1.0
  O  O19  1  0.664  0.424  0.837  1.0
  O  O20  1  0.623  0.873  0.750  1.0
  O  O21  1  0.377  0.127  0.250  1.0
[/CIF]
.