The structure described by Y5Si2B8 crystallizes in the tetragonal P4/mbm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to two equivalent B(3), three equivalent B(2), four equivalent B(1), and three equivalent Si(1) atoms. In the second Y site, Y(2) is bonded to two equivalent B(3) and four equivalent Si(1) atoms to form corner-sharing YSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Y(1), one B(2), two equivalent B(1), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to six equivalent Y(1), one B(2), and two equivalent B(1) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Y(2), four equivalent Y(1), and four equivalent B(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Y(2), six equivalent Y(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Y5(SiB4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.237
_cell_length_b   7.237
_cell_length_c   8.120
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   425.241
_cell_formula_units_Z   2
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
  Y  Y0  1  0.681  0.181  0.224  1.0
  Y  Y1  1  0.319  0.819  0.776  1.0
  Y  Y2  1  0.319  0.819  0.224  1.0
  Y  Y3  1  0.819  0.681  0.224  1.0
  Y  Y4  1  0.819  0.681  0.776  1.0
  Y  Y5  1  0.681  0.181  0.776  1.0
  Y  Y6  1  0.181  0.319  0.776  1.0
  Y  Y7  1  0.181  0.319  0.224  1.0
  Y  Y8  1  0.000  0.000  0.500  1.0
  Y  Y9  1  0.500  0.500  0.500  1.0
  Si  Si10  1  0.115  0.615  0.500  1.0
  Si  Si11  1  0.885  0.385  0.500  1.0
  Si  Si12  1  0.385  0.115  0.500  1.0
  Si  Si13  1  0.615  0.885  0.500  1.0
  B  B14  1  0.172  0.039  0.000  1.0
  B  B15  1  0.828  0.961  0.000  1.0
  B  B16  1  0.961  0.172  0.000  1.0
  B  B17  1  0.328  0.539  0.000  1.0
  B  B18  1  0.039  0.828  0.000  1.0
  B  B19  1  0.672  0.461  0.000  1.0
  B  B20  1  0.539  0.672  0.000  1.0
  B  B21  1  0.461  0.328  0.000  1.0
  B  B22  1  0.091  0.591  0.000  1.0
  B  B23  1  0.909  0.409  0.000  1.0
  B  B24  1  0.409  0.091  0.000  1.0
  B  B25  1  0.591  0.909  0.000  1.0
  B  B26  1  0.000  0.000  0.161  1.0
  B  B27  1  0.000  0.000  0.839  1.0
  B  B28  1  0.500  0.500  0.839  1.0
  B  B29  1  0.500  0.500  0.161  1.0
[/CIF]
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The structure described by Y5Si2B8 crystallizes in the tetragonal P4/mbm space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to two equivalent B(3), three equivalent B(2), four equivalent B(1), and three equivalent Si(1) atoms. In the second Y site, Y(2) is bonded to two equivalent B(3) and four equivalent Si(1) atoms to form corner-sharing YSi4B2 octahedra. The corner-sharing octahedral tilt angles are 57°. There are three inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to four equivalent Y(1), one B(2), two equivalent B(1), and two equivalent B(3) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to six equivalent Y(1), one B(2), and two equivalent B(1) atoms. In the third B site, B(3) is bonded in a 9-coordinate geometry to one Y(2), four equivalent Y(1), and four equivalent B(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Y(2), six equivalent Y(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Y5(SiB4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.237
_cell_length_b   7.237
_cell_length_c   8.120
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   425.241
_cell_formula_units_Z   2
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
  Y  Y0  1  0.681  0.181  0.224  1.0
  Y  Y1  1  0.319  0.819  0.776  1.0
  Y  Y2  1  0.319  0.819  0.224  1.0
  Y  Y3  1  0.819  0.681  0.224  1.0
  Y  Y4  1  0.819  0.681  0.776  1.0
  Y  Y5  1  0.681  0.181  0.776  1.0
  Y  Y6  1  0.181  0.319  0.776  1.0
  Y  Y7  1  0.181  0.319  0.224  1.0
  Y  Y8  1  0.000  0.000  0.500  1.0
  Y  Y9  1  0.500  0.500  0.500  1.0
  Si  Si10  1  0.115  0.615  0.500  1.0
  Si  Si11  1  0.885  0.385  0.500  1.0
  Si  Si12  1  0.385  0.115  0.500  1.0
  Si  Si13  1  0.615  0.885  0.500  1.0
  B  B14  1  0.172  0.039  0.000  1.0
  B  B15  1  0.828  0.961  0.000  1.0
  B  B16  1  0.961  0.172  0.000  1.0
  B  B17  1  0.328  0.539  0.000  1.0
  B  B18  1  0.039  0.828  0.000  1.0
  B  B19  1  0.672  0.461  0.000  1.0
  B  B20  1  0.539  0.672  0.000  1.0
  B  B21  1  0.461  0.328  0.000  1.0
  B  B22  1  0.091  0.591  0.000  1.0
  B  B23  1  0.909  0.409  0.000  1.0
  B  B24  1  0.409  0.091  0.000  1.0
  B  B25  1  0.591  0.909  0.000  1.0
  B  B26  1  0.000  0.000  0.161  1.0
  B  B27  1  0.000  0.000  0.839  1.0
  B  B28  1  0.500  0.500  0.839  1.0
  B  B29  1  0.500  0.500  0.161  1.0
[/CIF]
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