The compound described by Yb2PbSe4 is Orthorhombic Perovskite-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to one Se(2), two equivalent Se(4), and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing YbSe6 octahedra. In the second Yb site, Yb(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(3) atoms to form a mixture of distorted corner and edge-sharing YbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 46-61°. Pb(1) is bonded in a 5-coordinate geometry to one Se(4), two equivalent Se(1), and two equivalent Se(2) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Yb(1) and two equivalent Pb(1) atoms to form distorted edge-sharing SeYb3Pb2 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Yb(1), two equivalent Yb(2), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to three equivalent Yb(2) atoms. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to one Yb(2), two equivalent Yb(1), and one Pb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Yb2PbSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.075
_cell_length_b   13.839
_cell_length_c   13.831
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   779.897
_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  0.584  0.098  1.0
  Yb  Yb1  1  0.250  0.084  0.402  1.0
  Yb  Yb2  1  0.750  0.416  0.902  1.0
  Yb  Yb3  1  0.750  0.916  0.598  1.0
  Yb  Yb4  1  0.250  0.591  0.592  1.0
  Yb  Yb5  1  0.250  0.091  0.908  1.0
  Yb  Yb6  1  0.750  0.409  0.408  1.0
  Yb  Yb7  1  0.750  0.909  0.092  1.0
  Pb  Pb8  1  0.250  0.734  0.826  1.0
  Pb  Pb9  1  0.250  0.234  0.674  1.0
  Pb  Pb10  1  0.750  0.266  0.174  1.0
  Pb  Pb11  1  0.750  0.766  0.326  1.0
  Se  Se12  1  0.250  0.876  0.452  1.0
  Se  Se13  1  0.250  0.376  0.048  1.0
  Se  Se14  1  0.750  0.124  0.548  1.0
  Se  Se15  1  0.750  0.624  0.952  1.0
  Se  Se16  1  0.250  0.779  0.162  1.0
  Se  Se17  1  0.250  0.279  0.338  1.0
  Se  Se18  1  0.750  0.221  0.838  1.0
  Se  Se19  1  0.750  0.721  0.662  1.0
  Se  Se20  1  0.250  0.570  0.379  1.0
  Se  Se21  1  0.250  0.070  0.121  1.0
  Se  Se22  1  0.750  0.430  0.621  1.0
  Se  Se23  1  0.750  0.930  0.879  1.0
  Se  Se24  1  0.250  0.509  0.783  1.0
  Se  Se25  1  0.250  0.009  0.717  1.0
  Se  Se26  1  0.750  0.491  0.217  1.0
  Se  Se27  1  0.750  0.991  0.283  1.0
[/CIF]
.
The compound described by Yb2PbSe4 is Orthorhombic Perovskite-like structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Yb sites. In the first Yb site, Yb(1) is bonded to one Se(2), two equivalent Se(4), and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing YbSe6 octahedra. In the second Yb site, Yb(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(3) atoms to form a mixture of distorted corner and edge-sharing YbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 46-61°. Pb(1) is bonded in a 5-coordinate geometry to one Se(4), two equivalent Se(1), and two equivalent Se(2) atoms. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Yb(1) and two equivalent Pb(1) atoms to form distorted edge-sharing SeYb3Pb2 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Yb(1), two equivalent Yb(2), and two equivalent Pb(1) atoms. In the third Se site, Se(3) is bonded in a 3-coordinate geometry to three equivalent Yb(2) atoms. In the fourth Se site, Se(4) is bonded in a 3-coordinate geometry to one Yb(2), two equivalent Yb(1), and one Pb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Yb2PbSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.075
_cell_length_b   13.839
_cell_length_c   13.831
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   779.897
_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  0.584  0.098  1.0
  Yb  Yb1  1  0.250  0.084  0.402  1.0
  Yb  Yb2  1  0.750  0.416  0.902  1.0
  Yb  Yb3  1  0.750  0.916  0.598  1.0
  Yb  Yb4  1  0.250  0.591  0.592  1.0
  Yb  Yb5  1  0.250  0.091  0.908  1.0
  Yb  Yb6  1  0.750  0.409  0.408  1.0
  Yb  Yb7  1  0.750  0.909  0.092  1.0
  Pb  Pb8  1  0.250  0.734  0.826  1.0
  Pb  Pb9  1  0.250  0.234  0.674  1.0
  Pb  Pb10  1  0.750  0.266  0.174  1.0
  Pb  Pb11  1  0.750  0.766  0.326  1.0
  Se  Se12  1  0.250  0.876  0.452  1.0
  Se  Se13  1  0.250  0.376  0.048  1.0
  Se  Se14  1  0.750  0.124  0.548  1.0
  Se  Se15  1  0.750  0.624  0.952  1.0
  Se  Se16  1  0.250  0.779  0.162  1.0
  Se  Se17  1  0.250  0.279  0.338  1.0
  Se  Se18  1  0.750  0.221  0.838  1.0
  Se  Se19  1  0.750  0.721  0.662  1.0
  Se  Se20  1  0.250  0.570  0.379  1.0
  Se  Se21  1  0.250  0.070  0.121  1.0
  Se  Se22  1  0.750  0.430  0.621  1.0
  Se  Se23  1  0.750  0.930  0.879  1.0
  Se  Se24  1  0.250  0.509  0.783  1.0
  Se  Se25  1  0.250  0.009  0.717  1.0
  Se  Se26  1  0.750  0.491  0.217  1.0
  Se  Se27  1  0.750  0.991  0.283  1.0
[/CIF]
.