The compound described by La2RhSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to twelve equivalent Si(1) atoms to form LaSi12 cuboctahedra that share edges with twelve equivalent La(2)Si8Rh4 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with six equivalent La(2)Si8Rh4 cuboctahedra. In the second La site, La(2) is bonded to four equivalent Rh(1) and eight equivalent Si(1) atoms to form LaSi8Rh4 cuboctahedra that share edges with four equivalent La(1)Si12 cuboctahedra, edges with eight equivalent La(2)Si8Rh4 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with six equivalent La(2)Si8Rh4 cuboctahedra. Rh(1) is bonded in a 9-coordinate geometry to six equivalent La(2) and three equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent La(1), four equivalent La(2), one Rh(1), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_La2Si3Rh
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.305
_cell_length_b   8.337
_cell_length_c   8.337
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   259.101
_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
  La  La0  1  0.500  0.000  0.000  1.0
  La  La1  1  0.500  0.500  0.000  1.0
  La  La2  1  0.500  0.500  0.500  1.0
  La  La3  1  0.500  1.000  0.500  1.0
  Rh  Rh4  1  0.000  0.667  0.333  1.0
  Rh  Rh5  1  1.000  0.333  0.667  1.0
  Si  Si6  1  1.000  0.834  0.668  1.0
  Si  Si7  1  0.000  0.834  0.166  1.0
  Si  Si8  1  0.000  0.332  0.166  1.0
  Si  Si9  1  0.000  0.166  0.332  1.0
  Si  Si10  1  0.000  0.166  0.834  1.0
  Si  Si11  1  0.000  0.668  0.834  1.0
[/CIF]
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The compound described by La2RhSi3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to twelve equivalent Si(1) atoms to form LaSi12 cuboctahedra that share edges with twelve equivalent La(2)Si8Rh4 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with six equivalent La(2)Si8Rh4 cuboctahedra. In the second La site, La(2) is bonded to four equivalent Rh(1) and eight equivalent Si(1) atoms to form LaSi8Rh4 cuboctahedra that share edges with four equivalent La(1)Si12 cuboctahedra, edges with eight equivalent La(2)Si8Rh4 cuboctahedra, faces with two equivalent La(1)Si12 cuboctahedra, and faces with six equivalent La(2)Si8Rh4 cuboctahedra. Rh(1) is bonded in a 9-coordinate geometry to six equivalent La(2) and three equivalent Si(1) atoms. Si(1) is bonded in a 9-coordinate geometry to two equivalent La(1), four equivalent La(2), one Rh(1), and two equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_La2Si3Rh
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.305
_cell_length_b   8.337
_cell_length_c   8.337
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   259.101
_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
  La  La0  1  0.500  0.000  0.000  1.0
  La  La1  1  0.500  0.500  0.000  1.0
  La  La2  1  0.500  0.500  0.500  1.0
  La  La3  1  0.500  1.000  0.500  1.0
  Rh  Rh4  1  0.000  0.667  0.333  1.0
  Rh  Rh5  1  1.000  0.333  0.667  1.0
  Si  Si6  1  1.000  0.834  0.668  1.0
  Si  Si7  1  0.000  0.834  0.166  1.0
  Si  Si8  1  0.000  0.332  0.166  1.0
  Si  Si9  1  0.000  0.166  0.332  1.0
  Si  Si10  1  0.000  0.166  0.834  1.0
  Si  Si11  1  0.000  0.668  0.834  1.0
[/CIF]
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