The material described by Er2FeSi2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to two equivalent Fe(1), one Si(2), and five equivalent Si(1) atoms. In the second Er site, Er(2) is bonded in a 10-coordinate geometry to four equivalent Fe(1), two equivalent Si(1), and five equivalent Si(2) atoms. Fe(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), five equivalent Er(1), one Fe(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Er(1), five equivalent Er(2), three equivalent Fe(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Er2FeSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.104
_cell_length_b   5.556
_cell_length_c   8.826
_cell_angle_alpha   82.885
_cell_angle_beta   76.556
_cell_angle_gamma   68.328
_symmetry_Int_Tables_number   1
_cell_volume   181.744
_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
  Er  Er0  1  0.188  0.732  0.891  1.0
  Er  Er1  1  0.812  0.268  0.109  1.0
  Er  Er2  1  0.001  0.328  0.671  1.0
  Er  Er3  1  0.999  0.672  0.329  1.0
  Fe  Fe4  1  0.730  0.918  0.623  1.0
  Fe  Fe5  1  0.270  0.082  0.377  1.0
  Si  Si6  1  0.500  0.128  0.873  1.0
  Si  Si7  1  0.500  0.872  0.127  1.0
  Si  Si8  1  0.345  0.745  0.564  1.0
  Si  Si9  1  0.655  0.255  0.436  1.0
[/CIF]
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The material described by Er2FeSi2 crystallizes in the monoclinic C2/m space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to two equivalent Fe(1), one Si(2), and five equivalent Si(1) atoms. In the second Er site, Er(2) is bonded in a 10-coordinate geometry to four equivalent Fe(1), two equivalent Si(1), and five equivalent Si(2) atoms. Fe(1) is bonded in a 10-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(2), five equivalent Er(1), one Fe(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to one Er(1), five equivalent Er(2), three equivalent Fe(1), and one Si(2) atom. is represented by the CIF card [CIF]
data_Er2FeSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.104
_cell_length_b   5.556
_cell_length_c   8.826
_cell_angle_alpha   82.885
_cell_angle_beta   76.556
_cell_angle_gamma   68.328
_symmetry_Int_Tables_number   1
_cell_volume   181.744
_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
  Er  Er0  1  0.188  0.732  0.891  1.0
  Er  Er1  1  0.812  0.268  0.109  1.0
  Er  Er2  1  0.001  0.328  0.671  1.0
  Er  Er3  1  0.999  0.672  0.329  1.0
  Fe  Fe4  1  0.730  0.918  0.623  1.0
  Fe  Fe5  1  0.270  0.082  0.377  1.0
  Si  Si6  1  0.500  0.128  0.873  1.0
  Si  Si7  1  0.500  0.872  0.127  1.0
  Si  Si8  1  0.345  0.745  0.564  1.0
  Si  Si9  1  0.655  0.255  0.436  1.0
[/CIF]
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