The material described by Er5Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to one Si(3), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. In the third Er site, Er(3) is bonded to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms to form distorted corner-sharing ErSi6 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Er(3), three equivalent Er(2), four equivalent Er(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Er(2), two equivalent Er(3), four equivalent Er(1), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(3), four equivalent Er(2), and one Si(2) atom. is represented by the CIF file [CIF]
data_Er5Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.342
_cell_length_b   7.600
_cell_length_c   14.373
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   802.022
_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
  Er  Er0  1  0.029  0.818  0.401  1.0
  Er  Er1  1  0.529  0.682  0.401  1.0
  Er  Er2  1  0.317  0.820  0.877  1.0
  Er  Er3  1  0.817  0.680  0.877  1.0
  Er  Er4  1  0.852  0.511  0.250  1.0
  Er  Er5  1  0.471  0.318  0.901  1.0
  Er  Er6  1  0.029  0.818  0.099  1.0
  Er  Er7  1  0.471  0.318  0.599  1.0
  Er  Er8  1  0.648  0.011  0.750  1.0
  Er  Er9  1  0.529  0.682  0.099  1.0
  Er  Er10  1  0.683  0.180  0.123  1.0
  Er  Er11  1  0.183  0.320  0.377  1.0
  Er  Er12  1  0.183  0.320  0.123  1.0
  Er  Er13  1  0.817  0.680  0.623  1.0
  Er  Er14  1  0.317  0.820  0.623  1.0
  Er  Er15  1  0.352  0.989  0.250  1.0
  Er  Er16  1  0.683  0.180  0.377  1.0
  Er  Er17  1  0.148  0.489  0.750  1.0
  Er  Er18  1  0.971  0.182  0.901  1.0
  Er  Er19  1  0.971  0.182  0.599  1.0
  Si  Si20  1  0.647  0.972  0.540  1.0
  Si  Si21  1  0.233  0.629  0.250  1.0
  Si  Si22  1  0.353  0.028  0.460  1.0
  Si  Si23  1  0.020  0.895  0.750  1.0
  Si  Si24  1  0.733  0.871  0.250  1.0
  Si  Si25  1  0.267  0.129  0.750  1.0
  Si  Si26  1  0.853  0.472  0.460  1.0
  Si  Si27  1  0.480  0.395  0.250  1.0
  Si  Si28  1  0.147  0.528  0.540  1.0
  Si  Si29  1  0.147  0.528  0.960  1.0
  Si  Si30  1  0.980  0.105  0.250  1.0
  Si  Si31  1  0.767  0.371  0.750  1.0
  Si  Si32  1  0.353  0.028  0.040  1.0
  Si  Si33  1  0.853  0.472  0.040  1.0
  Si  Si34  1  0.647  0.972  0.960  1.0
  Si  Si35  1  0.520  0.605  0.750  1.0
[/CIF]
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The material described by Er5Si4 crystallizes in the orthorhombic Pnma space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 6-coordinate geometry to one Si(3), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Er site, Er(2) is bonded in a 6-coordinate geometry to one Si(2), two equivalent Si(3), and three equivalent Si(1) atoms. In the third Er site, Er(3) is bonded to two equivalent Si(1), two equivalent Si(2), and two equivalent Si(3) atoms to form distorted corner-sharing ErSi6 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to one Er(3), three equivalent Er(2), four equivalent Er(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Er(2), two equivalent Er(3), four equivalent Er(1), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Er(1), two equivalent Er(3), four equivalent Er(2), and one Si(2) atom. is represented by the CIF file [CIF]
data_Er5Si4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.342
_cell_length_b   7.600
_cell_length_c   14.373
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   802.022
_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
  Er  Er0  1  0.029  0.818  0.401  1.0
  Er  Er1  1  0.529  0.682  0.401  1.0
  Er  Er2  1  0.317  0.820  0.877  1.0
  Er  Er3  1  0.817  0.680  0.877  1.0
  Er  Er4  1  0.852  0.511  0.250  1.0
  Er  Er5  1  0.471  0.318  0.901  1.0
  Er  Er6  1  0.029  0.818  0.099  1.0
  Er  Er7  1  0.471  0.318  0.599  1.0
  Er  Er8  1  0.648  0.011  0.750  1.0
  Er  Er9  1  0.529  0.682  0.099  1.0
  Er  Er10  1  0.683  0.180  0.123  1.0
  Er  Er11  1  0.183  0.320  0.377  1.0
  Er  Er12  1  0.183  0.320  0.123  1.0
  Er  Er13  1  0.817  0.680  0.623  1.0
  Er  Er14  1  0.317  0.820  0.623  1.0
  Er  Er15  1  0.352  0.989  0.250  1.0
  Er  Er16  1  0.683  0.180  0.377  1.0
  Er  Er17  1  0.148  0.489  0.750  1.0
  Er  Er18  1  0.971  0.182  0.901  1.0
  Er  Er19  1  0.971  0.182  0.599  1.0
  Si  Si20  1  0.647  0.972  0.540  1.0
  Si  Si21  1  0.233  0.629  0.250  1.0
  Si  Si22  1  0.353  0.028  0.460  1.0
  Si  Si23  1  0.020  0.895  0.750  1.0
  Si  Si24  1  0.733  0.871  0.250  1.0
  Si  Si25  1  0.267  0.129  0.750  1.0
  Si  Si26  1  0.853  0.472  0.460  1.0
  Si  Si27  1  0.480  0.395  0.250  1.0
  Si  Si28  1  0.147  0.528  0.540  1.0
  Si  Si29  1  0.147  0.528  0.960  1.0
  Si  Si30  1  0.980  0.105  0.250  1.0
  Si  Si31  1  0.767  0.371  0.750  1.0
  Si  Si32  1  0.353  0.028  0.040  1.0
  Si  Si33  1  0.853  0.472  0.040  1.0
  Si  Si34  1  0.647  0.972  0.960  1.0
  Si  Si35  1  0.520  0.605  0.750  1.0
[/CIF]
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