The material described by Eu2Si is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to five equivalent Si(1) atoms. In the second Eu site, Eu(2) is bonded to four equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing EuSi4 tetrahedra. Si(1) is bonded in a 9-coordinate geometry to four equivalent Eu(2) and five equivalent Eu(1) atoms. is represented by the CIF file [CIF]
data_Eu2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.964
_cell_length_b   7.606
_cell_length_c   9.367
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   353.679
_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
  Eu  Eu0  1  0.250  0.522  0.818  1.0
  Eu  Eu1  1  0.250  0.022  0.682  1.0
  Eu  Eu2  1  0.750  0.478  0.182  1.0
  Eu  Eu3  1  0.750  0.978  0.318  1.0
  Eu  Eu4  1  0.250  0.657  0.422  1.0
  Eu  Eu5  1  0.250  0.157  0.077  1.0
  Eu  Eu6  1  0.750  0.343  0.578  1.0
  Eu  Eu7  1  0.750  0.843  0.923  1.0
  Si  Si8  1  0.250  0.748  0.105  1.0
  Si  Si9  1  0.250  0.248  0.395  1.0
  Si  Si10  1  0.750  0.252  0.895  1.0
  Si  Si11  1  0.750  0.752  0.605  1.0
[/CIF]
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The material described by Eu2Si is Cotunnite structured and crystallizes in the orthorhombic Pnma space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to five equivalent Si(1) atoms. In the second Eu site, Eu(2) is bonded to four equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing EuSi4 tetrahedra. Si(1) is bonded in a 9-coordinate geometry to four equivalent Eu(2) and five equivalent Eu(1) atoms. is represented by the CIF file [CIF]
data_Eu2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.964
_cell_length_b   7.606
_cell_length_c   9.367
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   353.679
_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
  Eu  Eu0  1  0.250  0.522  0.818  1.0
  Eu  Eu1  1  0.250  0.022  0.682  1.0
  Eu  Eu2  1  0.750  0.478  0.182  1.0
  Eu  Eu3  1  0.750  0.978  0.318  1.0
  Eu  Eu4  1  0.250  0.657  0.422  1.0
  Eu  Eu5  1  0.250  0.157  0.077  1.0
  Eu  Eu6  1  0.750  0.343  0.578  1.0
  Eu  Eu7  1  0.750  0.843  0.923  1.0
  Si  Si8  1  0.250  0.748  0.105  1.0
  Si  Si9  1  0.250  0.248  0.395  1.0
  Si  Si10  1  0.750  0.252  0.895  1.0
  Si  Si11  1  0.750  0.752  0.605  1.0
[/CIF]
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