The crystal structure described by Sm2Cr2Fe15 crystallizes in the trigonal R-3m space group. Sm(1) is bonded in a 19-coordinate geometry to one Cr(1), three equivalent Fe(2), six equivalent Fe(3), and nine equivalent Fe(1) atoms. Cr(1) is bonded in a 14-coordinate geometry to one Sm(1), one Cr(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Sm(1), one Cr(1), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form FeSm3CrFe8 cuboctahedra that share corners with five equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, corners with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra, edges with two equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with three equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, edges with five equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with three equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with seven equivalent Fe(1)Sm3CrFe8 cuboctahedra, and faces with ten equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Sm(1), two equivalent Cr(1), four equivalent Fe(1), and four equivalent Fe(3) atoms to form distorted FeSm2Cr2Fe8 cuboctahedra that share corners with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, corners with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra, edges with four equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with six equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with six equivalent Fe(1)Sm3CrFe8 cuboctahedra, and faces with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra. In the third Fe site, Fe(3) is bonded to two equivalent Sm(1), two equivalent Cr(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms to form distorted FeSm2Cr2Fe8 cuboctahedra that share corners with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(1)Sm3CrFe8 cuboctahedra, corners with twelve equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra,  an edgeedge with one Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with two equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, edges with two equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with seven equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, and faces with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra. is represented by the CIF file [CIF]
data_Sm2Cr2Fe15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.401
_cell_length_b   6.401
_cell_length_c   6.401
_cell_angle_alpha   82.286
_cell_angle_beta   82.286
_cell_angle_gamma   82.286
_symmetry_Int_Tables_number   1
_cell_volume   255.709
_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  0.658  0.658  0.658  1.0
  Sm  Sm1  1  0.342  0.342  0.342  1.0
  Cr  Cr2  1  0.086  0.086  0.086  1.0
  Cr  Cr3  1  0.914  0.914  0.914  1.0
  Fe  Fe4  1  0.339  0.339  0.845  1.0
  Fe  Fe5  1  0.845  0.339  0.339  1.0
  Fe  Fe6  1  0.000  0.000  0.500  1.0
  Fe  Fe7  1  0.000  0.500  0.000  1.0
  Fe  Fe8  1  0.500  0.000  0.000  1.0
  Fe  Fe9  1  0.702  0.298  0.000  1.0
  Fe  Fe10  1  0.298  0.000  0.702  1.0
  Fe  Fe11  1  0.000  0.702  0.298  1.0
  Fe  Fe12  1  0.298  0.702  0.000  1.0
  Fe  Fe13  1  0.702  0.000  0.298  1.0
  Fe  Fe14  1  0.000  0.298  0.702  1.0
  Fe  Fe15  1  0.155  0.661  0.661  1.0
  Fe  Fe16  1  0.661  0.661  0.155  1.0
  Fe  Fe17  1  0.661  0.155  0.661  1.0
  Fe  Fe18  1  0.339  0.845  0.339  1.0
[/CIF]
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The crystal structure described by Sm2Cr2Fe15 crystallizes in the trigonal R-3m space group. Sm(1) is bonded in a 19-coordinate geometry to one Cr(1), three equivalent Fe(2), six equivalent Fe(3), and nine equivalent Fe(1) atoms. Cr(1) is bonded in a 14-coordinate geometry to one Sm(1), one Cr(1), three equivalent Fe(1), three equivalent Fe(2), and six equivalent Fe(3) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to three equivalent Sm(1), one Cr(1), two equivalent Fe(1), two equivalent Fe(2), and four equivalent Fe(3) atoms to form FeSm3CrFe8 cuboctahedra that share corners with five equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, corners with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra, edges with two equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with three equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, edges with five equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with three equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with seven equivalent Fe(1)Sm3CrFe8 cuboctahedra, and faces with ten equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Sm(1), two equivalent Cr(1), four equivalent Fe(1), and four equivalent Fe(3) atoms to form distorted FeSm2Cr2Fe8 cuboctahedra that share corners with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, corners with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra, edges with four equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with six equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with six equivalent Fe(1)Sm3CrFe8 cuboctahedra, and faces with eight equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra. In the third Fe site, Fe(3) is bonded to two equivalent Sm(1), two equivalent Cr(1), two equivalent Fe(2), two equivalent Fe(3), and four equivalent Fe(1) atoms to form distorted FeSm2Cr2Fe8 cuboctahedra that share corners with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, corners with eight equivalent Fe(1)Sm3CrFe8 cuboctahedra, corners with twelve equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra,  an edgeedge with one Fe(3)Sm2Cr2Fe8 cuboctahedra, edges with two equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, edges with two equivalent Fe(1)Sm3CrFe8 cuboctahedra, faces with four equivalent Fe(2)Sm2Cr2Fe8 cuboctahedra, faces with seven equivalent Fe(3)Sm2Cr2Fe8 cuboctahedra, and faces with ten equivalent Fe(1)Sm3CrFe8 cuboctahedra. is represented by the CIF file [CIF]
data_Sm2Cr2Fe15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.401
_cell_length_b   6.401
_cell_length_c   6.401
_cell_angle_alpha   82.286
_cell_angle_beta   82.286
_cell_angle_gamma   82.286
_symmetry_Int_Tables_number   1
_cell_volume   255.709
_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  0.658  0.658  0.658  1.0
  Sm  Sm1  1  0.342  0.342  0.342  1.0
  Cr  Cr2  1  0.086  0.086  0.086  1.0
  Cr  Cr3  1  0.914  0.914  0.914  1.0
  Fe  Fe4  1  0.339  0.339  0.845  1.0
  Fe  Fe5  1  0.845  0.339  0.339  1.0
  Fe  Fe6  1  0.000  0.000  0.500  1.0
  Fe  Fe7  1  0.000  0.500  0.000  1.0
  Fe  Fe8  1  0.500  0.000  0.000  1.0
  Fe  Fe9  1  0.702  0.298  0.000  1.0
  Fe  Fe10  1  0.298  0.000  0.702  1.0
  Fe  Fe11  1  0.000  0.702  0.298  1.0
  Fe  Fe12  1  0.298  0.702  0.000  1.0
  Fe  Fe13  1  0.702  0.000  0.298  1.0
  Fe  Fe14  1  0.000  0.298  0.702  1.0
  Fe  Fe15  1  0.155  0.661  0.661  1.0
  Fe  Fe16  1  0.661  0.661  0.155  1.0
  Fe  Fe17  1  0.661  0.155  0.661  1.0
  Fe  Fe18  1  0.339  0.845  0.339  1.0
[/CIF]
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