The compound described by Yb3Se4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 8-coordinate geometry to one Se(4), two equivalent Se(1), two equivalent Se(2), and three equivalent Se(3) atoms. In the second Yb site, Yb(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form YbSe6 octahedra that share  a cornercorner with one Se(2)Yb5Se octahedra, corners with two equivalent Se(1)Yb5Se octahedra, corners with three equivalent Yb(3)Se6 octahedra, edges with two equivalent Yb(3)Se6 octahedra, and edges with four equivalent Yb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 23-86°. In the third Yb site, Yb(3) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form YbSe6 octahedra that share  a cornercorner with one Se(1)Yb5Se octahedra, corners with two equivalent Se(2)Yb5Se octahedra, corners with three equivalent Yb(2)Se6 octahedra, edges with two equivalent Yb(2)Se6 octahedra, and edges with two equivalent Yb(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 43-86°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Yb(2), two equivalent Yb(1), two equivalent Yb(3), and one Se(2) atom to form distorted SeYb5Se octahedra that share  a cornercorner with one Yb(3)Se6 octahedra, corners with two equivalent Yb(2)Se6 octahedra, corners with two equivalent Se(2)Yb5Se octahedra, corners with six equivalent Se(3)Yb5 square pyramids, corners with three equivalent Se(4)Yb5 trigonal bipyramids, edges with two equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(2)Yb5Se octahedra, edges with two equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 43-81°. In the second Se site, Se(2) is bonded to one Yb(3), two equivalent Yb(1), two equivalent Yb(2), and one Se(1) atom to form distorted SeYb5Se octahedra that share  a cornercorner with one Yb(2)Se6 octahedra, corners with two equivalent Yb(3)Se6 octahedra, corners with two equivalent Se(1)Yb5Se octahedra, corners with two equivalent Se(3)Yb5 square pyramids, corners with seven equivalent Se(4)Yb5 trigonal bipyramids, edges with two equivalent Se(2)Yb5Se octahedra, edges with three equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(3)Yb5 square pyramids, and  an edgeedge with one Se(4)Yb5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 23-81°. In the third Se site, Se(3) is bonded to two equivalent Yb(3) and three equivalent Yb(1) atoms to form distorted SeYb5 square pyramids that share corners with two equivalent Se(2)Yb5Se octahedra, corners with six equivalent Se(1)Yb5Se octahedra,  a cornercorner with one Se(4)Yb5 trigonal bipyramid, edges with two equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(2)Yb5Se octahedra, edges with four equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 10-55°. In the fourth Se site, Se(4) is bonded to one Yb(1), one Yb(3), and three equivalent Yb(2) atoms to form SeYb5 trigonal bipyramids that share corners with three equivalent Se(1)Yb5Se octahedra, corners with seven equivalent Se(2)Yb5Se octahedra,  a cornercorner with one Se(3)Yb5 square pyramid, corners with two equivalent Se(4)Yb5 trigonal bipyramids,  an edgeedge with one Se(2)Yb5Se octahedra, edges with two equivalent Se(1)Yb5Se octahedra, edges with two equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 4-79°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Yb3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.292
_cell_length_b   12.048
_cell_length_c   14.752
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   762.767
_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
  Yb  Yb0  1  0.250  0.119  0.098  1.0
  Yb  Yb1  1  0.750  0.881  0.902  1.0
  Yb  Yb2  1  0.250  0.381  0.598  1.0
  Yb  Yb3  1  0.750  0.619  0.402  1.0
  Yb  Yb4  1  0.750  0.455  0.106  1.0
  Yb  Yb5  1  0.250  0.545  0.894  1.0
  Yb  Yb6  1  0.750  0.045  0.606  1.0
  Yb  Yb7  1  0.250  0.955  0.394  1.0
  Yb  Yb8  1  0.250  0.300  0.362  1.0
  Yb  Yb9  1  0.750  0.700  0.638  1.0
  Yb  Yb10  1  0.250  0.200  0.862  1.0
  Yb  Yb11  1  0.750  0.800  0.138  1.0
  Se  Se12  1  0.750  0.225  0.226  1.0
  Se  Se13  1  0.250  0.775  0.774  1.0
  Se  Se14  1  0.750  0.275  0.726  1.0
  Se  Se15  1  0.250  0.725  0.274  1.0
  Se  Se16  1  0.250  0.523  0.245  1.0
  Se  Se17  1  0.750  0.477  0.755  1.0
  Se  Se18  1  0.250  0.977  0.745  1.0
  Se  Se19  1  0.750  0.023  0.255  1.0
  Se  Se20  1  0.750  0.390  0.463  1.0
  Se  Se21  1  0.250  0.610  0.537  1.0
  Se  Se22  1  0.750  0.110  0.963  1.0
  Se  Se23  1  0.250  0.890  0.037  1.0
  Se  Se24  1  0.250  0.144  0.509  1.0
  Se  Se25  1  0.750  0.856  0.491  1.0
  Se  Se26  1  0.250  0.356  0.009  1.0
  Se  Se27  1  0.750  0.644  0.991  1.0
[/CIF]
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The compound described by Yb3Se4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Yb sites. In the first Yb site, Yb(1) is bonded in a 8-coordinate geometry to one Se(4), two equivalent Se(1), two equivalent Se(2), and three equivalent Se(3) atoms. In the second Yb site, Yb(2) is bonded to one Se(1), two equivalent Se(2), and three equivalent Se(4) atoms to form YbSe6 octahedra that share  a cornercorner with one Se(2)Yb5Se octahedra, corners with two equivalent Se(1)Yb5Se octahedra, corners with three equivalent Yb(3)Se6 octahedra, edges with two equivalent Yb(3)Se6 octahedra, and edges with four equivalent Yb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 23-86°. In the third Yb site, Yb(3) is bonded to one Se(2), one Se(4), two equivalent Se(1), and two equivalent Se(3) atoms to form YbSe6 octahedra that share  a cornercorner with one Se(1)Yb5Se octahedra, corners with two equivalent Se(2)Yb5Se octahedra, corners with three equivalent Yb(2)Se6 octahedra, edges with two equivalent Yb(2)Se6 octahedra, and edges with two equivalent Yb(3)Se6 octahedra. The corner-sharing octahedral tilt angles range from 43-86°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Yb(2), two equivalent Yb(1), two equivalent Yb(3), and one Se(2) atom to form distorted SeYb5Se octahedra that share  a cornercorner with one Yb(3)Se6 octahedra, corners with two equivalent Yb(2)Se6 octahedra, corners with two equivalent Se(2)Yb5Se octahedra, corners with six equivalent Se(3)Yb5 square pyramids, corners with three equivalent Se(4)Yb5 trigonal bipyramids, edges with two equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(2)Yb5Se octahedra, edges with two equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 43-81°. In the second Se site, Se(2) is bonded to one Yb(3), two equivalent Yb(1), two equivalent Yb(2), and one Se(1) atom to form distorted SeYb5Se octahedra that share  a cornercorner with one Yb(2)Se6 octahedra, corners with two equivalent Yb(3)Se6 octahedra, corners with two equivalent Se(1)Yb5Se octahedra, corners with two equivalent Se(3)Yb5 square pyramids, corners with seven equivalent Se(4)Yb5 trigonal bipyramids, edges with two equivalent Se(2)Yb5Se octahedra, edges with three equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(3)Yb5 square pyramids, and  an edgeedge with one Se(4)Yb5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 23-81°. In the third Se site, Se(3) is bonded to two equivalent Yb(3) and three equivalent Yb(1) atoms to form distorted SeYb5 square pyramids that share corners with two equivalent Se(2)Yb5Se octahedra, corners with six equivalent Se(1)Yb5Se octahedra,  a cornercorner with one Se(4)Yb5 trigonal bipyramid, edges with two equivalent Se(1)Yb5Se octahedra, edges with three equivalent Se(2)Yb5Se octahedra, edges with four equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 10-55°. In the fourth Se site, Se(4) is bonded to one Yb(1), one Yb(3), and three equivalent Yb(2) atoms to form SeYb5 trigonal bipyramids that share corners with three equivalent Se(1)Yb5Se octahedra, corners with seven equivalent Se(2)Yb5Se octahedra,  a cornercorner with one Se(3)Yb5 square pyramid, corners with two equivalent Se(4)Yb5 trigonal bipyramids,  an edgeedge with one Se(2)Yb5Se octahedra, edges with two equivalent Se(1)Yb5Se octahedra, edges with two equivalent Se(3)Yb5 square pyramids, and edges with two equivalent Se(4)Yb5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 4-79°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Yb3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.292
_cell_length_b   12.048
_cell_length_c   14.752
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   762.767
_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
  Yb  Yb0  1  0.250  0.119  0.098  1.0
  Yb  Yb1  1  0.750  0.881  0.902  1.0
  Yb  Yb2  1  0.250  0.381  0.598  1.0
  Yb  Yb3  1  0.750  0.619  0.402  1.0
  Yb  Yb4  1  0.750  0.455  0.106  1.0
  Yb  Yb5  1  0.250  0.545  0.894  1.0
  Yb  Yb6  1  0.750  0.045  0.606  1.0
  Yb  Yb7  1  0.250  0.955  0.394  1.0
  Yb  Yb8  1  0.250  0.300  0.362  1.0
  Yb  Yb9  1  0.750  0.700  0.638  1.0
  Yb  Yb10  1  0.250  0.200  0.862  1.0
  Yb  Yb11  1  0.750  0.800  0.138  1.0
  Se  Se12  1  0.750  0.225  0.226  1.0
  Se  Se13  1  0.250  0.775  0.774  1.0
  Se  Se14  1  0.750  0.275  0.726  1.0
  Se  Se15  1  0.250  0.725  0.274  1.0
  Se  Se16  1  0.250  0.523  0.245  1.0
  Se  Se17  1  0.750  0.477  0.755  1.0
  Se  Se18  1  0.250  0.977  0.745  1.0
  Se  Se19  1  0.750  0.023  0.255  1.0
  Se  Se20  1  0.750  0.390  0.463  1.0
  Se  Se21  1  0.250  0.610  0.537  1.0
  Se  Se22  1  0.750  0.110  0.963  1.0
  Se  Se23  1  0.250  0.890  0.037  1.0
  Se  Se24  1  0.250  0.144  0.509  1.0
  Se  Se25  1  0.750  0.856  0.491  1.0
  Se  Se26  1  0.250  0.356  0.009  1.0
  Se  Se27  1  0.750  0.644  0.991  1.0
[/CIF]
.