The compound described by Ce2SnSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 7-coordinate geometry to one Se(2), one Se(3), two equivalent Se(4), and three equivalent Se(1) atoms. In the second Ce site, Ce(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(3) atoms to form edge-sharing CeSe6 octahedra. Sn(1) is bonded in a 5-coordinate geometry to one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded to one Ce(1), two equivalent Ce(2), and one Sn(1) atom to form SeCe3Sn trigonal pyramids that share corners with three equivalent Se(3)Ce4Sn2 octahedra, corners with two equivalent Se(4)Ce3Sn2 trigonal bipyramids, corners with two equivalent Se(2)Ce3Sn trigonal pyramids, edges with three equivalent Se(3)Ce4Sn2 octahedra, and edges with two equivalent Se(4)Ce3Sn2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 3-41°. In the third Se site, Se(3) is bonded to one Ce(1), three equivalent Ce(2), and two equivalent Sn(1) atoms to form distorted SeCe4Sn2 octahedra that share corners with three equivalent Se(4)Ce3Sn2 trigonal bipyramids, corners with three equivalent Se(2)Ce3Sn trigonal pyramids, edges with four equivalent Se(3)Ce4Sn2 octahedra, edges with three equivalent Se(4)Ce3Sn2 trigonal bipyramids, and edges with three equivalent Se(2)Ce3Sn trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Ce(2), two equivalent Ce(1), and two equivalent Sn(1) atoms to form distorted SeCe3Sn2 trigonal bipyramids that share corners with three equivalent Se(3)Ce4Sn2 octahedra, corners with two equivalent Se(2)Ce3Sn trigonal pyramids, edges with three equivalent Se(3)Ce4Sn2 octahedra, edges with two equivalent Se(4)Ce3Sn2 trigonal bipyramids, and edges with two equivalent Se(2)Ce3Sn trigonal pyramids. The corner-sharing octahedral tilt angles range from 2-18°. is represented by the CIF file [CIF]
data_Ce2SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.300
_cell_length_b   12.274
_cell_length_c   15.317
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   808.359
_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
  Ce  Ce0  1  0.250  0.604  0.096  1.0
  Ce  Ce1  1  0.750  0.896  0.596  1.0
  Ce  Ce2  1  0.250  0.062  0.897  1.0
  Ce  Ce3  1  0.750  0.438  0.397  1.0
  Ce  Ce4  1  0.250  0.562  0.603  1.0
  Ce  Ce5  1  0.750  0.938  0.103  1.0
  Ce  Ce6  1  0.750  0.396  0.904  1.0
  Ce  Ce7  1  0.250  0.104  0.404  1.0
  Sn  Sn8  1  0.750  0.264  0.662  1.0
  Sn  Sn9  1  0.250  0.236  0.162  1.0
  Sn  Sn10  1  0.750  0.764  0.838  1.0
  Sn  Sn11  1  0.250  0.736  0.338  1.0
  Se  Se12  1  0.750  0.943  0.410  1.0
  Se  Se13  1  0.250  0.557  0.910  1.0
  Se  Se14  1  0.750  0.443  0.090  1.0
  Se  Se15  1  0.250  0.057  0.590  1.0
  Se  Se16  1  0.750  0.482  0.712  1.0
  Se  Se17  1  0.250  0.018  0.212  1.0
  Se  Se18  1  0.750  0.982  0.788  1.0
  Se  Se19  1  0.250  0.518  0.288  1.0
  Se  Se20  1  0.750  0.658  0.488  1.0
  Se  Se21  1  0.250  0.842  0.988  1.0
  Se  Se22  1  0.750  0.158  0.012  1.0
  Se  Se23  1  0.250  0.342  0.512  1.0
  Se  Se24  1  0.750  0.734  0.196  1.0
  Se  Se25  1  0.250  0.766  0.696  1.0
  Se  Se26  1  0.750  0.234  0.304  1.0
  Se  Se27  1  0.250  0.266  0.804  1.0
[/CIF]
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The compound described by Ce2SnSe4 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded in a 7-coordinate geometry to one Se(2), one Se(3), two equivalent Se(4), and three equivalent Se(1) atoms. In the second Ce site, Ce(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(3) atoms to form edge-sharing CeSe6 octahedra. Sn(1) is bonded in a 5-coordinate geometry to one Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ce(1) atoms. In the second Se site, Se(2) is bonded to one Ce(1), two equivalent Ce(2), and one Sn(1) atom to form SeCe3Sn trigonal pyramids that share corners with three equivalent Se(3)Ce4Sn2 octahedra, corners with two equivalent Se(4)Ce3Sn2 trigonal bipyramids, corners with two equivalent Se(2)Ce3Sn trigonal pyramids, edges with three equivalent Se(3)Ce4Sn2 octahedra, and edges with two equivalent Se(4)Ce3Sn2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 3-41°. In the third Se site, Se(3) is bonded to one Ce(1), three equivalent Ce(2), and two equivalent Sn(1) atoms to form distorted SeCe4Sn2 octahedra that share corners with three equivalent Se(4)Ce3Sn2 trigonal bipyramids, corners with three equivalent Se(2)Ce3Sn trigonal pyramids, edges with four equivalent Se(3)Ce4Sn2 octahedra, edges with three equivalent Se(4)Ce3Sn2 trigonal bipyramids, and edges with three equivalent Se(2)Ce3Sn trigonal pyramids. In the fourth Se site, Se(4) is bonded to one Ce(2), two equivalent Ce(1), and two equivalent Sn(1) atoms to form distorted SeCe3Sn2 trigonal bipyramids that share corners with three equivalent Se(3)Ce4Sn2 octahedra, corners with two equivalent Se(2)Ce3Sn trigonal pyramids, edges with three equivalent Se(3)Ce4Sn2 octahedra, edges with two equivalent Se(4)Ce3Sn2 trigonal bipyramids, and edges with two equivalent Se(2)Ce3Sn trigonal pyramids. The corner-sharing octahedral tilt angles range from 2-18°. is represented by the CIF file [CIF]
data_Ce2SnSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.300
_cell_length_b   12.274
_cell_length_c   15.317
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   808.359
_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
  Ce  Ce0  1  0.250  0.604  0.096  1.0
  Ce  Ce1  1  0.750  0.896  0.596  1.0
  Ce  Ce2  1  0.250  0.062  0.897  1.0
  Ce  Ce3  1  0.750  0.438  0.397  1.0
  Ce  Ce4  1  0.250  0.562  0.603  1.0
  Ce  Ce5  1  0.750  0.938  0.103  1.0
  Ce  Ce6  1  0.750  0.396  0.904  1.0
  Ce  Ce7  1  0.250  0.104  0.404  1.0
  Sn  Sn8  1  0.750  0.264  0.662  1.0
  Sn  Sn9  1  0.250  0.236  0.162  1.0
  Sn  Sn10  1  0.750  0.764  0.838  1.0
  Sn  Sn11  1  0.250  0.736  0.338  1.0
  Se  Se12  1  0.750  0.943  0.410  1.0
  Se  Se13  1  0.250  0.557  0.910  1.0
  Se  Se14  1  0.750  0.443  0.090  1.0
  Se  Se15  1  0.250  0.057  0.590  1.0
  Se  Se16  1  0.750  0.482  0.712  1.0
  Se  Se17  1  0.250  0.018  0.212  1.0
  Se  Se18  1  0.750  0.982  0.788  1.0
  Se  Se19  1  0.250  0.518  0.288  1.0
  Se  Se20  1  0.750  0.658  0.488  1.0
  Se  Se21  1  0.250  0.842  0.988  1.0
  Se  Se22  1  0.750  0.158  0.012  1.0
  Se  Se23  1  0.250  0.342  0.512  1.0
  Se  Se24  1  0.750  0.734  0.196  1.0
  Se  Se25  1  0.250  0.766  0.696  1.0
  Se  Se26  1  0.750  0.234  0.304  1.0
  Se  Se27  1  0.250  0.266  0.804  1.0
[/CIF]
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