The compound described by Y2FeSi2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 10-coordinate geometry to four equivalent Fe(1), two equivalent Si(2), and five equivalent Si(1) atoms. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to two equivalent Fe(1), one Si(1), and five equivalent Si(2) atoms. Fe(1) is bonded in a 10-coordinate geometry to two equivalent Y(2), four equivalent Y(1), one Si(2), and three equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to one Y(2), five equivalent Y(1), three equivalent Fe(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Y(1), five equivalent Y(2), one Fe(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Y2FeSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.643
_cell_length_b   5.643
_cell_length_c   10.159
_cell_angle_alpha   63.463
_cell_angle_beta   63.463
_cell_angle_gamma   43.247
_symmetry_Int_Tables_number   1
_cell_volume   194.383
_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  0.995  0.995  0.328  1.0
  Y  Y1  1  0.005  0.005  0.672  1.0
  Y  Y2  1  0.810  0.810  0.107  1.0
  Y  Y3  1  0.190  0.190  0.893  1.0
  Fe  Fe4  1  0.722  0.722  0.637  1.0
  Fe  Fe5  1  0.278  0.278  0.363  1.0
  Si  Si6  1  0.644  0.644  0.439  1.0
  Si  Si7  1  0.356  0.356  0.561  1.0
  Si  Si8  1  0.505  0.505  0.121  1.0
  Si  Si9  1  0.495  0.495  0.879  1.0
[/CIF]
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The compound described by Y2FeSi2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 10-coordinate geometry to four equivalent Fe(1), two equivalent Si(2), and five equivalent Si(1) atoms. In the second Y site, Y(2) is bonded in a 8-coordinate geometry to two equivalent Fe(1), one Si(1), and five equivalent Si(2) atoms. Fe(1) is bonded in a 10-coordinate geometry to two equivalent Y(2), four equivalent Y(1), one Si(2), and three equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 10-coordinate geometry to one Y(2), five equivalent Y(1), three equivalent Fe(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Y(1), five equivalent Y(2), one Fe(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Y2FeSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.643
_cell_length_b   5.643
_cell_length_c   10.159
_cell_angle_alpha   63.463
_cell_angle_beta   63.463
_cell_angle_gamma   43.247
_symmetry_Int_Tables_number   1
_cell_volume   194.383
_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  0.995  0.995  0.328  1.0
  Y  Y1  1  0.005  0.005  0.672  1.0
  Y  Y2  1  0.810  0.810  0.107  1.0
  Y  Y3  1  0.190  0.190  0.893  1.0
  Fe  Fe4  1  0.722  0.722  0.637  1.0
  Fe  Fe5  1  0.278  0.278  0.363  1.0
  Si  Si6  1  0.644  0.644  0.439  1.0
  Si  Si7  1  0.356  0.356  0.561  1.0
  Si  Si8  1  0.505  0.505  0.121  1.0
  Si  Si9  1  0.495  0.495  0.879  1.0
[/CIF]
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