The structure described by La3Ni4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 14-coordinate geometry to four equivalent Ni(1), four equivalent Ni(2), two equivalent Si(2), and four equivalent Si(1) atoms. In the second La site, La(2) is bonded to four equivalent Ni(2) and eight equivalent Si(2) atoms to form a mixture of face and edge-sharing LaSi8Ni4 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 8-coordinate geometry to four equivalent La(1) and four equivalent Si(1) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to two equivalent La(2), four equivalent La(1), one Si(1), and two 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 four equivalent La(1), one Ni(2), and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent La(1), four equivalent La(2), two equivalent Ni(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3(SiNi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.155
_cell_length_b   12.155
_cell_length_c   12.155
_cell_angle_alpha   160.491
_cell_angle_beta   160.236
_cell_angle_gamma   27.911
_symmetry_Int_Tables_number   1
_cell_volume   202.726
_cell_formula_units_Z   1
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  0.850  0.350  0.500  1.0
  La  La1  1  0.000  0.000  0.000  1.0
  La  La2  1  0.150  0.650  0.500  1.0
  Si  Si3  1  0.701  0.201  0.500  1.0
  Si  Si4  1  0.448  0.448  0.000  1.0
  Si  Si5  1  0.552  0.552  0.000  1.0
  Si  Si6  1  0.299  0.799  0.500  1.0
  Ni  Ni7  1  0.249  0.249  0.000  1.0
  Ni  Ni8  1  0.751  0.751  0.000  1.0
  Ni  Ni9  1  0.600  0.100  0.500  1.0
  Ni  Ni10  1  0.400  0.900  0.500  1.0
[/CIF]
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The structure described by La3Ni4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 14-coordinate geometry to four equivalent Ni(1), four equivalent Ni(2), two equivalent Si(2), and four equivalent Si(1) atoms. In the second La site, La(2) is bonded to four equivalent Ni(2) and eight equivalent Si(2) atoms to form a mixture of face and edge-sharing LaSi8Ni4 cuboctahedra. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 8-coordinate geometry to four equivalent La(1) and four equivalent Si(1) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to two equivalent La(2), four equivalent La(1), one Si(1), and two 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 four equivalent La(1), one Ni(2), and four equivalent Ni(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent La(1), four equivalent La(2), two equivalent Ni(2), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_La3(SiNi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.155
_cell_length_b   12.155
_cell_length_c   12.155
_cell_angle_alpha   160.491
_cell_angle_beta   160.236
_cell_angle_gamma   27.911
_symmetry_Int_Tables_number   1
_cell_volume   202.726
_cell_formula_units_Z   1
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  0.850  0.350  0.500  1.0
  La  La1  1  0.000  0.000  0.000  1.0
  La  La2  1  0.150  0.650  0.500  1.0
  Si  Si3  1  0.701  0.201  0.500  1.0
  Si  Si4  1  0.448  0.448  0.000  1.0
  Si  Si5  1  0.552  0.552  0.000  1.0
  Si  Si6  1  0.299  0.799  0.500  1.0
  Ni  Ni7  1  0.249  0.249  0.000  1.0
  Ni  Ni8  1  0.751  0.751  0.000  1.0
  Ni  Ni9  1  0.600  0.100  0.500  1.0
  Ni  Ni10  1  0.400  0.900  0.500  1.0
[/CIF]
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