The material described by Y5Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded in a 6-coordinate geometry to one Si(3), two equivalent Si(2), and three equivalent Si(1) atoms. In the second Y site, Y(2) is bonded to one Si(2), two equivalent Si(3), and three equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing YSi6 octahedra. The corner-sharing octahedral tilt angles range from 38-45°. In the third Y site, Y(3) is bonded to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing YSi6 octahedra. The corner-sharing octahedral tilt angles range from 44-56°. There are three inequivalent Si sites. In the first Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), four equivalent Y(2), and one Si(2) atom. In the second Si site, Si(1) is bonded in a 8-coordinate geometry to one Y(3), three equivalent Y(1), three equivalent Y(2), and one Si(1) atom. In the third Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Y(2), two equivalent Y(3), four equivalent Y(1), and one Si(3) atom. is represented by the CIF card [CIF]
data_Y5Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.457
_cell_length_b   7.691
_cell_length_c   14.633
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   839.267
_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
  Y  Y0  1  0.687  0.179  0.622  1.0
  Y  Y1  1  0.187  0.321  0.878  1.0
  Y  Y2  1  0.313  0.821  0.122  1.0
  Y  Y3  1  0.813  0.679  0.378  1.0
  Y  Y4  1  0.313  0.821  0.378  1.0
  Y  Y5  1  0.813  0.679  0.122  1.0
  Y  Y6  1  0.687  0.179  0.878  1.0
  Y  Y7  1  0.187  0.321  0.622  1.0
  Y  Y8  1  0.533  0.683  0.598  1.0
  Y  Y9  1  0.033  0.817  0.902  1.0
  Y  Y10  1  0.467  0.317  0.098  1.0
  Y  Y11  1  0.967  0.183  0.402  1.0
  Y  Y12  1  0.467  0.317  0.402  1.0
  Y  Y13  1  0.967  0.183  0.098  1.0
  Y  Y14  1  0.533  0.683  0.902  1.0
  Y  Y15  1  0.033  0.817  0.598  1.0
  Y  Y16  1  0.858  0.512  0.750  1.0
  Y  Y17  1  0.358  0.988  0.750  1.0
  Y  Y18  1  0.142  0.488  0.250  1.0
  Y  Y19  1  0.642  0.012  0.250  1.0
  Si  Si20  1  0.641  0.974  0.459  1.0
  Si  Si21  1  0.141  0.526  0.041  1.0
  Si  Si22  1  0.359  0.026  0.959  1.0
  Si  Si23  1  0.859  0.474  0.541  1.0
  Si  Si24  1  0.359  0.026  0.541  1.0
  Si  Si25  1  0.859  0.474  0.959  1.0
  Si  Si26  1  0.641  0.974  0.041  1.0
  Si  Si27  1  0.141  0.526  0.459  1.0
  Si  Si28  1  0.485  0.396  0.750  1.0
  Si  Si29  1  0.985  0.104  0.750  1.0
  Si  Si30  1  0.515  0.604  0.250  1.0
  Si  Si31  1  0.015  0.896  0.250  1.0
  Si  Si32  1  0.741  0.874  0.750  1.0
  Si  Si33  1  0.241  0.626  0.750  1.0
  Si  Si34  1  0.259  0.126  0.250  1.0
  Si  Si35  1  0.759  0.374  0.250  1.0
[/CIF]
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The material described by Y5Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Y sites. In the first Y site, Y(1) is bonded in a 6-coordinate geometry to one Si(3), two equivalent Si(2), and three equivalent Si(1) atoms. In the second Y site, Y(2) is bonded to one Si(2), two equivalent Si(3), and three equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing YSi6 octahedra. The corner-sharing octahedral tilt angles range from 38-45°. In the third Y site, Y(3) is bonded to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms to form a mixture of distorted face and corner-sharing YSi6 octahedra. The corner-sharing octahedral tilt angles range from 44-56°. There are three inequivalent Si sites. In the first Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Y(1), two equivalent Y(3), four equivalent Y(2), and one Si(2) atom. In the second Si site, Si(1) is bonded in a 8-coordinate geometry to one Y(3), three equivalent Y(1), three equivalent Y(2), and one Si(1) atom. In the third Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Y(2), two equivalent Y(3), four equivalent Y(1), and one Si(3) atom. is represented by the CIF card [CIF]
data_Y5Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.457
_cell_length_b   7.691
_cell_length_c   14.633
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.001
_symmetry_Int_Tables_number   1
_cell_volume   839.267
_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
  Y  Y0  1  0.687  0.179  0.622  1.0
  Y  Y1  1  0.187  0.321  0.878  1.0
  Y  Y2  1  0.313  0.821  0.122  1.0
  Y  Y3  1  0.813  0.679  0.378  1.0
  Y  Y4  1  0.313  0.821  0.378  1.0
  Y  Y5  1  0.813  0.679  0.122  1.0
  Y  Y6  1  0.687  0.179  0.878  1.0
  Y  Y7  1  0.187  0.321  0.622  1.0
  Y  Y8  1  0.533  0.683  0.598  1.0
  Y  Y9  1  0.033  0.817  0.902  1.0
  Y  Y10  1  0.467  0.317  0.098  1.0
  Y  Y11  1  0.967  0.183  0.402  1.0
  Y  Y12  1  0.467  0.317  0.402  1.0
  Y  Y13  1  0.967  0.183  0.098  1.0
  Y  Y14  1  0.533  0.683  0.902  1.0
  Y  Y15  1  0.033  0.817  0.598  1.0
  Y  Y16  1  0.858  0.512  0.750  1.0
  Y  Y17  1  0.358  0.988  0.750  1.0
  Y  Y18  1  0.142  0.488  0.250  1.0
  Y  Y19  1  0.642  0.012  0.250  1.0
  Si  Si20  1  0.641  0.974  0.459  1.0
  Si  Si21  1  0.141  0.526  0.041  1.0
  Si  Si22  1  0.359  0.026  0.959  1.0
  Si  Si23  1  0.859  0.474  0.541  1.0
  Si  Si24  1  0.359  0.026  0.541  1.0
  Si  Si25  1  0.859  0.474  0.959  1.0
  Si  Si26  1  0.641  0.974  0.041  1.0
  Si  Si27  1  0.141  0.526  0.459  1.0
  Si  Si28  1  0.485  0.396  0.750  1.0
  Si  Si29  1  0.985  0.104  0.750  1.0
  Si  Si30  1  0.515  0.604  0.250  1.0
  Si  Si31  1  0.015  0.896  0.250  1.0
  Si  Si32  1  0.741  0.874  0.750  1.0
  Si  Si33  1  0.241  0.626  0.750  1.0
  Si  Si34  1  0.259  0.126  0.250  1.0
  Si  Si35  1  0.759  0.374  0.250  1.0
[/CIF]
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