The material described by Yb5Se7 crystallizes in the monoclinic C2/m space group. There are three 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 YbSe6 octahedra that share  a cornercorner with one Yb(3)Se6 octahedra, corners with two equivalent Yb(1)Se6 octahedra, corners with two equivalent Yb(2)Se7 pentagonal bipyramids, edges with five equivalent Yb(1)Se6 octahedra, and edges with five equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 0-78°. In the second Yb site, Yb(2) is bonded to one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted YbSe7 pentagonal bipyramids that share corners with two equivalent Yb(1)Se6 octahedra, corners with four equivalent Yb(3)Se6 octahedra,  a cornercorner with one Yb(2)Se7 pentagonal bipyramid,  an edgeedge with one Yb(3)Se6 octahedra, edges with five equivalent Yb(1)Se6 octahedra, and faces with two equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-49°. In the third Yb site, Yb(3) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(1)Se6 octahedra, corners with eight equivalent Yb(2)Se7 pentagonal bipyramids, edges with two equivalent Yb(3)Se6 octahedra, and edges with two equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 78°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Yb(2), three equivalent Yb(1), and one Se(3) atom. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Yb(2), two equivalent Yb(3), and one Se(1) atom. In the fourth Se site, Se(4) is bonded to two equivalent Yb(2) and four equivalent Yb(1) atoms to form edge-sharing SeYb6 octahedra. is represented by the CIF file [CIF]
data_Yb5Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.823
_cell_length_b   7.823
_cell_length_c   11.779
_cell_angle_alpha   64.028
_cell_angle_beta   64.028
_cell_angle_gamma   31.046
_symmetry_Int_Tables_number   1
_cell_volume   331.149
_cell_formula_units_Z   1
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  0.914  0.914  0.904  1.0
  Yb  Yb1  1  0.086  0.086  0.096  1.0
  Yb  Yb2  1  0.680  0.680  0.738  1.0
  Yb  Yb3  1  0.320  0.320  0.262  1.0
  Yb  Yb4  1  0.000  0.000  0.500  1.0
  Se  Se5  1  0.287  0.287  0.859  1.0
  Se  Se6  1  0.713  0.713  0.141  1.0
  Se  Se7  1  0.916  0.916  0.331  1.0
  Se  Se8  1  0.084  0.084  0.669  1.0
  Se  Se9  1  0.343  0.343  0.628  1.0
  Se  Se10  1  0.657  0.657  0.372  1.0
  Se  Se11  1  0.500  0.500  0.000  1.0
[/CIF]
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The material described by Yb5Se7 crystallizes in the monoclinic C2/m space group. There are three 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 YbSe6 octahedra that share  a cornercorner with one Yb(3)Se6 octahedra, corners with two equivalent Yb(1)Se6 octahedra, corners with two equivalent Yb(2)Se7 pentagonal bipyramids, edges with five equivalent Yb(1)Se6 octahedra, and edges with five equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 0-78°. In the second Yb site, Yb(2) is bonded to one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(3) atoms to form distorted YbSe7 pentagonal bipyramids that share corners with two equivalent Yb(1)Se6 octahedra, corners with four equivalent Yb(3)Se6 octahedra,  a cornercorner with one Yb(2)Se7 pentagonal bipyramid,  an edgeedge with one Yb(3)Se6 octahedra, edges with five equivalent Yb(1)Se6 octahedra, and faces with two equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles range from 5-49°. In the third Yb site, Yb(3) is bonded to two equivalent Se(2) and four equivalent Se(3) atoms to form YbSe6 octahedra that share corners with two equivalent Yb(1)Se6 octahedra, corners with eight equivalent Yb(2)Se7 pentagonal bipyramids, edges with two equivalent Yb(3)Se6 octahedra, and edges with two equivalent Yb(2)Se7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 78°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Yb(2), three equivalent Yb(1), and one Se(3) atom. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Yb(3), and two equivalent Yb(2) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Yb(2), two equivalent Yb(3), and one Se(1) atom. In the fourth Se site, Se(4) is bonded to two equivalent Yb(2) and four equivalent Yb(1) atoms to form edge-sharing SeYb6 octahedra. is represented by the CIF file [CIF]
data_Yb5Se7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.823
_cell_length_b   7.823
_cell_length_c   11.779
_cell_angle_alpha   64.028
_cell_angle_beta   64.028
_cell_angle_gamma   31.046
_symmetry_Int_Tables_number   1
_cell_volume   331.149
_cell_formula_units_Z   1
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  0.914  0.914  0.904  1.0
  Yb  Yb1  1  0.086  0.086  0.096  1.0
  Yb  Yb2  1  0.680  0.680  0.738  1.0
  Yb  Yb3  1  0.320  0.320  0.262  1.0
  Yb  Yb4  1  0.000  0.000  0.500  1.0
  Se  Se5  1  0.287  0.287  0.859  1.0
  Se  Se6  1  0.713  0.713  0.141  1.0
  Se  Se7  1  0.916  0.916  0.331  1.0
  Se  Se8  1  0.084  0.084  0.669  1.0
  Se  Se9  1  0.343  0.343  0.628  1.0
  Se  Se10  1  0.657  0.657  0.372  1.0
  Se  Se11  1  0.500  0.500  0.000  1.0
[/CIF]
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