The material described by Sm3CuSe6 crystallizes in the orthorhombic Pca2_1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 8-coordinate geometry to one Se(4), one Se(5), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(6) atoms. In the second Sm site, Sm(2) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(5), one Se(6), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. In the third Sm site, Sm(3) is bonded in a 9-coordinate geometry to one Cu(1), one Se(4), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(5) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Sm(3), two equivalent Sm(2), one Se(1), one Se(5), and two equivalent Se(4) atoms. There are six inequivalent Se sites. In the first Se site, Se(6) is bonded to one Sm(2), one Sm(3), and two equivalent Sm(1) atoms to form distorted corner-sharing SeSm4 trigonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), one Cu(1), and one Se(3) atom. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and one Se(3) atom. In the fourth Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), one Se(1), and one Se(2) atom. In the fifth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(2), and two equivalent Cu(1) atoms. In the sixth Se site, Se(5) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(2), two equivalent Sm(3), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm3CuSe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.180
_cell_length_b   7.900
_cell_length_c   17.085
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   969.193
_cell_formula_units_Z   4
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  0.266  0.945  0.247  1.0
  Sm  Sm1  1  0.734  0.055  0.747  1.0
  Sm  Sm2  1  0.266  0.555  0.747  1.0
  Sm  Sm3  1  0.734  0.445  0.247  1.0
  Sm  Sm4  1  0.226  0.555  0.412  1.0
  Sm  Sm5  1  0.774  0.445  0.912  1.0
  Sm  Sm6  1  0.243  0.941  0.590  1.0
  Sm  Sm7  1  0.757  0.059  0.090  1.0
  Sm  Sm8  1  0.757  0.441  0.590  1.0
  Sm  Sm9  1  0.243  0.559  0.090  1.0
  Sm  Sm10  1  0.774  0.055  0.412  1.0
  Sm  Sm11  1  0.226  0.945  0.912  1.0
  Cu  Cu12  1  0.405  0.210  0.478  1.0
  Cu  Cu13  1  0.595  0.790  0.978  1.0
  Cu  Cu14  1  0.595  0.710  0.478  1.0
  Cu  Cu15  1  0.405  0.290  0.978  1.0
  Se  Se16  1  0.076  0.248  0.500  1.0
  Se  Se17  1  0.924  0.752  0.000  1.0
  Se  Se18  1  0.924  0.748  0.500  1.0
  Se  Se19  1  0.076  0.252  0.000  1.0
  Se  Se20  1  0.075  0.252  0.321  1.0
  Se  Se21  1  0.925  0.748  0.821  1.0
  Se  Se22  1  0.074  0.247  0.675  1.0
  Se  Se23  1  0.926  0.753  0.175  1.0
  Se  Se24  1  0.926  0.747  0.675  1.0
  Se  Se25  1  0.074  0.253  0.175  1.0
  Se  Se26  1  0.925  0.752  0.321  1.0
  Se  Se27  1  0.075  0.248  0.821  1.0
  Se  Se28  1  0.389  0.910  0.417  1.0
  Se  Se29  1  0.611  0.090  0.917  1.0
  Se  Se30  1  0.384  0.596  0.580  1.0
  Se  Se31  1  0.616  0.404  0.080  1.0
  Se  Se32  1  0.616  0.096  0.580  1.0
  Se  Se33  1  0.384  0.904  0.080  1.0
  Se  Se34  1  0.611  0.410  0.417  1.0
  Se  Se35  1  0.389  0.590  0.917  1.0
  Se  Se36  1  0.379  0.600  0.251  1.0
  Se  Se37  1  0.621  0.400  0.751  1.0
  Se  Se38  1  0.379  0.900  0.751  1.0
  Se  Se39  1  0.621  0.100  0.251  1.0
[/CIF]
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The material described by Sm3CuSe6 crystallizes in the orthorhombic Pca2_1 space group. There are three inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 8-coordinate geometry to one Se(4), one Se(5), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(6) atoms. In the second Sm site, Sm(2) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(5), one Se(6), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(4) atoms. In the third Sm site, Sm(3) is bonded in a 9-coordinate geometry to one Cu(1), one Se(4), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(5) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Sm(3), two equivalent Sm(2), one Se(1), one Se(5), and two equivalent Se(4) atoms. There are six inequivalent Se sites. In the first Se site, Se(6) is bonded to one Sm(2), one Sm(3), and two equivalent Sm(1) atoms to form distorted corner-sharing SeSm4 trigonal pyramids. In the second Se site, Se(1) is bonded in a 5-coordinate geometry to two equivalent Sm(2), two equivalent Sm(3), one Cu(1), and one Se(3) atom. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Sm(1), two equivalent Sm(2), and one Se(3) atom. In the fourth Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Sm(1), two equivalent Sm(3), one Se(1), and one Se(2) atom. In the fifth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(2), and two equivalent Cu(1) atoms. In the sixth Se site, Se(5) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(2), two equivalent Sm(3), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm3CuSe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.180
_cell_length_b   7.900
_cell_length_c   17.085
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   969.193
_cell_formula_units_Z   4
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  0.266  0.945  0.247  1.0
  Sm  Sm1  1  0.734  0.055  0.747  1.0
  Sm  Sm2  1  0.266  0.555  0.747  1.0
  Sm  Sm3  1  0.734  0.445  0.247  1.0
  Sm  Sm4  1  0.226  0.555  0.412  1.0
  Sm  Sm5  1  0.774  0.445  0.912  1.0
  Sm  Sm6  1  0.243  0.941  0.590  1.0
  Sm  Sm7  1  0.757  0.059  0.090  1.0
  Sm  Sm8  1  0.757  0.441  0.590  1.0
  Sm  Sm9  1  0.243  0.559  0.090  1.0
  Sm  Sm10  1  0.774  0.055  0.412  1.0
  Sm  Sm11  1  0.226  0.945  0.912  1.0
  Cu  Cu12  1  0.405  0.210  0.478  1.0
  Cu  Cu13  1  0.595  0.790  0.978  1.0
  Cu  Cu14  1  0.595  0.710  0.478  1.0
  Cu  Cu15  1  0.405  0.290  0.978  1.0
  Se  Se16  1  0.076  0.248  0.500  1.0
  Se  Se17  1  0.924  0.752  0.000  1.0
  Se  Se18  1  0.924  0.748  0.500  1.0
  Se  Se19  1  0.076  0.252  0.000  1.0
  Se  Se20  1  0.075  0.252  0.321  1.0
  Se  Se21  1  0.925  0.748  0.821  1.0
  Se  Se22  1  0.074  0.247  0.675  1.0
  Se  Se23  1  0.926  0.753  0.175  1.0
  Se  Se24  1  0.926  0.747  0.675  1.0
  Se  Se25  1  0.074  0.253  0.175  1.0
  Se  Se26  1  0.925  0.752  0.321  1.0
  Se  Se27  1  0.075  0.248  0.821  1.0
  Se  Se28  1  0.389  0.910  0.417  1.0
  Se  Se29  1  0.611  0.090  0.917  1.0
  Se  Se30  1  0.384  0.596  0.580  1.0
  Se  Se31  1  0.616  0.404  0.080  1.0
  Se  Se32  1  0.616  0.096  0.580  1.0
  Se  Se33  1  0.384  0.904  0.080  1.0
  Se  Se34  1  0.611  0.410  0.417  1.0
  Se  Se35  1  0.389  0.590  0.917  1.0
  Se  Se36  1  0.379  0.600  0.251  1.0
  Se  Se37  1  0.621  0.400  0.751  1.0
  Se  Se38  1  0.379  0.900  0.751  1.0
  Se  Se39  1  0.621  0.100  0.251  1.0
[/CIF]
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