The compound described by Tb3CuSe6 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. In the second Tb site, Tb(2) is bonded in a 9-coordinate geometry to one Cu(1), one Se(1), one Se(3), one Se(4), one Se(5), two equivalent Se(2), and two equivalent Se(6) atoms. In the third Tb site, Tb(3) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(2), one Se(3), one Se(4), one Se(5), two equivalent Se(1), and two equivalent Se(6) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(3), one Se(2), one Se(6), and two equivalent Se(1) atoms. There are six inequivalent Se sites. In the first Se site, Se(6) is bonded in a 5-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), one Cu(1), and one Se(5) atom. In the second Se site, Se(1) is bonded in a 6-coordinate geometry to one Tb(1), one Tb(2), two equivalent Tb(3), and two equivalent Cu(1) atoms. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Tb(1), one Tb(3), two equivalent Tb(2), and one Cu(1) atom. In the fourth Se site, Se(3) is bonded to one Tb(2), one Tb(3), and two equivalent Tb(1) atoms to form distorted corner-sharing SeTb4 trigonal pyramids. In the fifth Se site, Se(4) is bonded in a 5-coordinate geometry to one Tb(2), one Tb(3), two equivalent Tb(1), and one Se(5) atom. In the sixth Se site, Se(5) is bonded in a 6-coordinate geometry to one Tb(2), one Tb(3), two equivalent Tb(1), one Se(4), and one Se(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb3CuSe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.780
_cell_length_b   7.115
_cell_length_c   17.111
_cell_angle_alpha   89.605
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   947.075
_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
  Tb  Tb0  1  0.940  0.266  0.750  1.0
  Tb  Tb1  1  0.060  0.734  0.250  1.0
  Tb  Tb2  1  0.560  0.266  0.250  1.0
  Tb  Tb3  1  0.440  0.734  0.750  1.0
  Tb  Tb4  1  0.558  0.239  0.588  1.0
  Tb  Tb5  1  0.442  0.768  0.091  1.0
  Tb  Tb6  1  0.942  0.232  0.409  1.0
  Tb  Tb7  1  0.058  0.761  0.912  1.0
  Tb  Tb8  1  0.442  0.761  0.412  1.0
  Tb  Tb9  1  0.558  0.232  0.909  1.0
  Tb  Tb10  1  0.058  0.768  0.591  1.0
  Tb  Tb11  1  0.942  0.239  0.088  1.0
  Cu  Cu12  1  0.211  0.394  0.527  1.0
  Cu  Cu13  1  0.711  0.606  0.973  1.0
  Cu  Cu14  1  0.789  0.606  0.473  1.0
  Cu  Cu15  1  0.289  0.394  0.027  1.0
  Se  Se16  1  0.909  0.390  0.582  1.0
  Se  Se17  1  0.092  0.618  0.081  1.0
  Se  Se18  1  0.592  0.382  0.419  1.0
  Se  Se19  1  0.409  0.610  0.918  1.0
  Se  Se20  1  0.091  0.610  0.418  1.0
  Se  Se21  1  0.908  0.382  0.919  1.0
  Se  Se22  1  0.408  0.618  0.581  1.0
  Se  Se23  1  0.591  0.390  0.082  1.0
  Se  Se24  1  0.597  0.381  0.749  1.0
  Se  Se25  1  0.403  0.619  0.251  1.0
  Se  Se26  1  0.903  0.381  0.249  1.0
  Se  Se27  1  0.097  0.619  0.751  1.0
  Se  Se28  1  0.250  0.078  0.679  1.0
  Se  Se29  1  0.751  0.925  0.177  1.0
  Se  Se30  1  0.251  0.075  0.323  1.0
  Se  Se31  1  0.750  0.922  0.821  1.0
  Se  Se32  1  0.750  0.922  0.321  1.0
  Se  Se33  1  0.249  0.075  0.823  1.0
  Se  Se34  1  0.749  0.925  0.677  1.0
  Se  Se35  1  0.250  0.078  0.179  1.0
  Se  Se36  1  0.251  0.064  0.499  1.0
  Se  Se37  1  0.751  0.936  0.001  1.0
  Se  Se38  1  0.749  0.936  0.501  1.0
  Se  Se39  1  0.249  0.064  0.999  1.0
[/CIF]
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The compound described by Tb3CuSe6 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 8-coordinate geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent Se(5) atoms. In the second Tb site, Tb(2) is bonded in a 9-coordinate geometry to one Cu(1), one Se(1), one Se(3), one Se(4), one Se(5), two equivalent Se(2), and two equivalent Se(6) atoms. In the third Tb site, Tb(3) is bonded in a 10-coordinate geometry to two equivalent Cu(1), one Se(2), one Se(3), one Se(4), one Se(5), two equivalent Se(1), and two equivalent Se(6) atoms. Cu(1) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(3), one Se(2), one Se(6), and two equivalent Se(1) atoms. There are six inequivalent Se sites. In the first Se site, Se(6) is bonded in a 5-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), one Cu(1), and one Se(5) atom. In the second Se site, Se(1) is bonded in a 6-coordinate geometry to one Tb(1), one Tb(2), two equivalent Tb(3), and two equivalent Cu(1) atoms. In the third Se site, Se(2) is bonded in a 5-coordinate geometry to one Tb(1), one Tb(3), two equivalent Tb(2), and one Cu(1) atom. In the fourth Se site, Se(3) is bonded to one Tb(2), one Tb(3), and two equivalent Tb(1) atoms to form distorted corner-sharing SeTb4 trigonal pyramids. In the fifth Se site, Se(4) is bonded in a 5-coordinate geometry to one Tb(2), one Tb(3), two equivalent Tb(1), and one Se(5) atom. In the sixth Se site, Se(5) is bonded in a 6-coordinate geometry to one Tb(2), one Tb(3), two equivalent Tb(1), one Se(4), and one Se(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb3CuSe6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.780
_cell_length_b   7.115
_cell_length_c   17.111
_cell_angle_alpha   89.605
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   947.075
_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
  Tb  Tb0  1  0.940  0.266  0.750  1.0
  Tb  Tb1  1  0.060  0.734  0.250  1.0
  Tb  Tb2  1  0.560  0.266  0.250  1.0
  Tb  Tb3  1  0.440  0.734  0.750  1.0
  Tb  Tb4  1  0.558  0.239  0.588  1.0
  Tb  Tb5  1  0.442  0.768  0.091  1.0
  Tb  Tb6  1  0.942  0.232  0.409  1.0
  Tb  Tb7  1  0.058  0.761  0.912  1.0
  Tb  Tb8  1  0.442  0.761  0.412  1.0
  Tb  Tb9  1  0.558  0.232  0.909  1.0
  Tb  Tb10  1  0.058  0.768  0.591  1.0
  Tb  Tb11  1  0.942  0.239  0.088  1.0
  Cu  Cu12  1  0.211  0.394  0.527  1.0
  Cu  Cu13  1  0.711  0.606  0.973  1.0
  Cu  Cu14  1  0.789  0.606  0.473  1.0
  Cu  Cu15  1  0.289  0.394  0.027  1.0
  Se  Se16  1  0.909  0.390  0.582  1.0
  Se  Se17  1  0.092  0.618  0.081  1.0
  Se  Se18  1  0.592  0.382  0.419  1.0
  Se  Se19  1  0.409  0.610  0.918  1.0
  Se  Se20  1  0.091  0.610  0.418  1.0
  Se  Se21  1  0.908  0.382  0.919  1.0
  Se  Se22  1  0.408  0.618  0.581  1.0
  Se  Se23  1  0.591  0.390  0.082  1.0
  Se  Se24  1  0.597  0.381  0.749  1.0
  Se  Se25  1  0.403  0.619  0.251  1.0
  Se  Se26  1  0.903  0.381  0.249  1.0
  Se  Se27  1  0.097  0.619  0.751  1.0
  Se  Se28  1  0.250  0.078  0.679  1.0
  Se  Se29  1  0.751  0.925  0.177  1.0
  Se  Se30  1  0.251  0.075  0.323  1.0
  Se  Se31  1  0.750  0.922  0.821  1.0
  Se  Se32  1  0.750  0.922  0.321  1.0
  Se  Se33  1  0.249  0.075  0.823  1.0
  Se  Se34  1  0.749  0.925  0.677  1.0
  Se  Se35  1  0.250  0.078  0.179  1.0
  Se  Se36  1  0.251  0.064  0.499  1.0
  Se  Se37  1  0.751  0.936  0.001  1.0
  Se  Se38  1  0.749  0.936  0.501  1.0
  Se  Se39  1  0.249  0.064  0.999  1.0
[/CIF]
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