The material described by Er2RhSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to twelve equivalent Si(1) atoms to form ErSi12 cuboctahedra that share edges with twelve equivalent Er(2)Si8Rh4 cuboctahedra, faces with two equivalent Er(1)Si12 cuboctahedra, and faces with six equivalent Er(2)Si8Rh4 cuboctahedra. In the second Er site, Er(2) is bonded to four equivalent Rh(1) and eight equivalent Si(1) atoms to form ErSi8Rh4 cuboctahedra that share edges with four equivalent Er(1)Si12 cuboctahedra, edges with eight equivalent Er(2)Si8Rh4 cuboctahedra, faces with two equivalent Er(1)Si12 cuboctahedra, and faces with six equivalent Er(2)Si8Rh4 cuboctahedra. Rh(1) is bonded in a 9-coordinate geometry to six equivalent Er(2) and three equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Rh(1), and two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_Er2Si3Rh
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.924
_cell_length_b   8.158
_cell_length_c   8.158
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   226.154
_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  0.500  0.000  0.000  1.0
  Er  Er1  1  0.500  0.500  1.000  1.0
  Er  Er2  1  0.500  0.500  0.500  1.0
  Er  Er3  1  0.500  1.000  0.500  1.0
  Rh  Rh4  1  0.000  0.333  0.667  1.0
  Rh  Rh5  1  0.000  0.667  0.333  1.0
  Si  Si6  1  0.000  0.166  0.332  1.0
  Si  Si7  1  1.000  0.166  0.834  1.0
  Si  Si8  1  1.000  0.668  0.834  1.0
  Si  Si9  1  0.000  0.834  0.668  1.0
  Si  Si10  1  1.000  0.332  0.166  1.0
  Si  Si11  1  1.000  0.834  0.166  1.0
[/CIF]
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The material described by Er2RhSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to twelve equivalent Si(1) atoms to form ErSi12 cuboctahedra that share edges with twelve equivalent Er(2)Si8Rh4 cuboctahedra, faces with two equivalent Er(1)Si12 cuboctahedra, and faces with six equivalent Er(2)Si8Rh4 cuboctahedra. In the second Er site, Er(2) is bonded to four equivalent Rh(1) and eight equivalent Si(1) atoms to form ErSi8Rh4 cuboctahedra that share edges with four equivalent Er(1)Si12 cuboctahedra, edges with eight equivalent Er(2)Si8Rh4 cuboctahedra, faces with two equivalent Er(1)Si12 cuboctahedra, and faces with six equivalent Er(2)Si8Rh4 cuboctahedra. Rh(1) is bonded in a 9-coordinate geometry to six equivalent Er(2) and three equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent Er(1), four equivalent Er(2), one Rh(1), and two equivalent Si(1) atoms. is represented by the CIF file [CIF]
data_Er2Si3Rh
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.924
_cell_length_b   8.158
_cell_length_c   8.158
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   226.154
_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  0.500  0.000  0.000  1.0
  Er  Er1  1  0.500  0.500  1.000  1.0
  Er  Er2  1  0.500  0.500  0.500  1.0
  Er  Er3  1  0.500  1.000  0.500  1.0
  Rh  Rh4  1  0.000  0.333  0.667  1.0
  Rh  Rh5  1  0.000  0.667  0.333  1.0
  Si  Si6  1  0.000  0.166  0.332  1.0
  Si  Si7  1  1.000  0.166  0.834  1.0
  Si  Si8  1  1.000  0.668  0.834  1.0
  Si  Si9  1  0.000  0.834  0.668  1.0
  Si  Si10  1  1.000  0.332  0.166  1.0
  Si  Si11  1  1.000  0.834  0.166  1.0
[/CIF]
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