The material described by Sm3CuSe6 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(7) atoms. In the second Sm site, Sm(2) is bonded in a 9-coordinate geometry to one Cu(1), one Se(1), one Se(2), one Se(3), one Se(4), two equivalent Se(5), and two equivalent Se(7) atoms. In the third Sm site, Sm(3) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(3), one Se(4), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(5) atoms. In the fourth Sm site, Sm(4) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(3), one Se(5), one Se(7), and two equivalent Se(1) atoms. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sm(2), one Sm(4), two equivalent Sm(3), and two equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded to one Sm(1), one Sm(4), and two equivalent Sm(2) atoms to form distorted corner-sharing SeSm4 trigonal pyramids. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sm(1), one Sm(2), one Sm(3), one Sm(4), one Se(3), and one Se(5) atom. In the fourth Se site, Se(4) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(2), one Sm(3), one Sm(4), and one Se(4) atom. In the fifth Se site, Se(5) 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 sixth Se site, Se(6) is bonded to one Sm(1), one Sm(4), and two equivalent Sm(3) atoms to form corner-sharing SeSm4 trigonal pyramids. In the seventh Se site, Se(7) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(2), 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   17.073
_cell_length_b   7.182
_cell_length_c   7.918
_cell_angle_alpha   89.440
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   970.876
_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  0.750  0.765  0.443  1.0
  Sm  Sm1  1  0.587  0.256  0.559  1.0
  Sm  Sm2  1  0.409  0.274  0.944  1.0
  Sm  Sm3  1  0.091  0.274  0.944  1.0
  Sm  Sm4  1  0.909  0.726  0.056  1.0
  Sm  Sm5  1  0.750  0.233  0.946  1.0
  Sm  Sm6  1  0.413  0.744  0.441  1.0
  Sm  Sm7  1  0.087  0.744  0.441  1.0
  Sm  Sm8  1  0.591  0.726  0.056  1.0
  Sm  Sm9  1  0.250  0.235  0.557  1.0
  Sm  Sm10  1  0.250  0.767  0.054  1.0
  Sm  Sm11  1  0.913  0.256  0.559  1.0
  Cu  Cu12  1  0.471  0.895  0.798  1.0
  Cu  Cu13  1  0.971  0.105  0.202  1.0
  Cu  Cu14  1  0.529  0.105  0.202  1.0
  Cu  Cu15  1  0.029  0.895  0.798  1.0
  Se  Se16  1  0.581  0.108  0.910  1.0
  Se  Se17  1  0.081  0.892  0.090  1.0
  Se  Se18  1  0.250  0.885  0.396  1.0
  Se  Se19  1  0.177  0.431  0.250  1.0
  Se  Se20  1  0.419  0.892  0.090  1.0
  Se  Se21  1  0.822  0.421  0.256  1.0
  Se  Se22  1  1.000  0.573  0.748  1.0
  Se  Se23  1  0.677  0.569  0.750  1.0
  Se  Se24  1  0.823  0.569  0.750  1.0
  Se  Se25  1  0.750  0.873  0.097  1.0
  Se  Se26  1  0.419  0.114  0.600  1.0
  Se  Se27  1  0.500  0.427  0.252  1.0
  Se  Se28  1  0.919  0.886  0.400  1.0
  Se  Se29  1  0.178  0.579  0.744  1.0
  Se  Se30  1  0.750  0.115  0.604  1.0
  Se  Se31  1  0.500  0.573  0.748  1.0
  Se  Se32  1  0.678  0.421  0.256  1.0
  Se  Se33  1  0.581  0.886  0.400  1.0
  Se  Se34  1  0.323  0.431  0.250  1.0
  Se  Se35  1  0.322  0.579  0.744  1.0
  Se  Se36  1  0.000  0.427  0.252  1.0
  Se  Se37  1  0.081  0.114  0.600  1.0
  Se  Se38  1  0.250  0.127  0.903  1.0
  Se  Se39  1  0.919  0.108  0.910  1.0
[/CIF]
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The material described by Sm3CuSe6 crystallizes in the monoclinic P2_1/m space group. There are four inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(7) atoms. In the second Sm site, Sm(2) is bonded in a 9-coordinate geometry to one Cu(1), one Se(1), one Se(2), one Se(3), one Se(4), two equivalent Se(5), and two equivalent Se(7) atoms. In the third Sm site, Sm(3) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(3), one Se(4), one Se(6), one Se(7), two equivalent Se(1), and two equivalent Se(5) atoms. In the fourth Sm site, Sm(4) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(4) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Sm(2), two equivalent Sm(3), one Se(5), one Se(7), and two equivalent Se(1) atoms. There are seven inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sm(2), one Sm(4), two equivalent Sm(3), and two equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded to one Sm(1), one Sm(4), and two equivalent Sm(2) atoms to form distorted corner-sharing SeSm4 trigonal pyramids. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sm(1), one Sm(2), one Sm(3), one Sm(4), one Se(3), and one Se(5) atom. In the fourth Se site, Se(4) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(2), one Sm(3), one Sm(4), and one Se(4) atom. In the fifth Se site, Se(5) 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 sixth Se site, Se(6) is bonded to one Sm(1), one Sm(4), and two equivalent Sm(3) atoms to form corner-sharing SeSm4 trigonal pyramids. In the seventh Se site, Se(7) is bonded in a 5-coordinate geometry to one Sm(1), one Sm(3), two equivalent Sm(2), 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   17.073
_cell_length_b   7.182
_cell_length_c   7.918
_cell_angle_alpha   89.440
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   970.876
_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  0.750  0.765  0.443  1.0
  Sm  Sm1  1  0.587  0.256  0.559  1.0
  Sm  Sm2  1  0.409  0.274  0.944  1.0
  Sm  Sm3  1  0.091  0.274  0.944  1.0
  Sm  Sm4  1  0.909  0.726  0.056  1.0
  Sm  Sm5  1  0.750  0.233  0.946  1.0
  Sm  Sm6  1  0.413  0.744  0.441  1.0
  Sm  Sm7  1  0.087  0.744  0.441  1.0
  Sm  Sm8  1  0.591  0.726  0.056  1.0
  Sm  Sm9  1  0.250  0.235  0.557  1.0
  Sm  Sm10  1  0.250  0.767  0.054  1.0
  Sm  Sm11  1  0.913  0.256  0.559  1.0
  Cu  Cu12  1  0.471  0.895  0.798  1.0
  Cu  Cu13  1  0.971  0.105  0.202  1.0
  Cu  Cu14  1  0.529  0.105  0.202  1.0
  Cu  Cu15  1  0.029  0.895  0.798  1.0
  Se  Se16  1  0.581  0.108  0.910  1.0
  Se  Se17  1  0.081  0.892  0.090  1.0
  Se  Se18  1  0.250  0.885  0.396  1.0
  Se  Se19  1  0.177  0.431  0.250  1.0
  Se  Se20  1  0.419  0.892  0.090  1.0
  Se  Se21  1  0.822  0.421  0.256  1.0
  Se  Se22  1  1.000  0.573  0.748  1.0
  Se  Se23  1  0.677  0.569  0.750  1.0
  Se  Se24  1  0.823  0.569  0.750  1.0
  Se  Se25  1  0.750  0.873  0.097  1.0
  Se  Se26  1  0.419  0.114  0.600  1.0
  Se  Se27  1  0.500  0.427  0.252  1.0
  Se  Se28  1  0.919  0.886  0.400  1.0
  Se  Se29  1  0.178  0.579  0.744  1.0
  Se  Se30  1  0.750  0.115  0.604  1.0
  Se  Se31  1  0.500  0.573  0.748  1.0
  Se  Se32  1  0.678  0.421  0.256  1.0
  Se  Se33  1  0.581  0.886  0.400  1.0
  Se  Se34  1  0.323  0.431  0.250  1.0
  Se  Se35  1  0.322  0.579  0.744  1.0
  Se  Se36  1  0.000  0.427  0.252  1.0
  Se  Se37  1  0.081  0.114  0.600  1.0
  Se  Se38  1  0.250  0.127  0.903  1.0
  Se  Se39  1  0.919  0.108  0.910  1.0
[/CIF]
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