The crystal structure described by UCeSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. U(1) is bonded to four equivalent Si(1) and eight equivalent Si(2) atoms to form USi12 cuboctahedra that share edges with four equivalent U(1)Si12 cuboctahedra, edges with eight equivalent Ce(1)Si12 cuboctahedra, faces with four equivalent U(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. Ce(1) is bonded to four equivalent Si(2) and eight equivalent Si(1) atoms to form CeSi12 cuboctahedra that share edges with four equivalent Ce(1)Si12 cuboctahedra, edges with eight equivalent U(1)Si12 cuboctahedra, faces with four equivalent U(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent U(1), four equivalent Ce(1), one Si(1), and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent U(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_CeUSi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.637
_cell_length_b   7.637
_cell_length_c   7.637
_cell_angle_alpha   149.688
_cell_angle_beta   149.688
_cell_angle_gamma   43.399
_symmetry_Int_Tables_number   1
_cell_volume   113.151
_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
  Ce  Ce0  1  0.250  0.750  0.500  1.0
  U  U1  1  0.000  0.000  0.000  1.0
  Si  Si2  1  0.665  0.165  0.500  1.0
  Si  Si3  1  0.581  0.581  0.000  1.0
  Si  Si4  1  0.835  0.335  0.500  1.0
  Si  Si5  1  0.419  0.419  0.000  1.0
[/CIF]
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The crystal structure described by UCeSi4 is hexagonal omega structure-derived structured and crystallizes in the tetragonal I-4m2 space group. U(1) is bonded to four equivalent Si(1) and eight equivalent Si(2) atoms to form USi12 cuboctahedra that share edges with four equivalent U(1)Si12 cuboctahedra, edges with eight equivalent Ce(1)Si12 cuboctahedra, faces with four equivalent U(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. Ce(1) is bonded to four equivalent Si(2) and eight equivalent Si(1) atoms to form CeSi12 cuboctahedra that share edges with four equivalent Ce(1)Si12 cuboctahedra, edges with eight equivalent U(1)Si12 cuboctahedra, faces with four equivalent U(1)Si12 cuboctahedra, and faces with four equivalent Ce(1)Si12 cuboctahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent U(1), four equivalent Ce(1), one Si(1), and two equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to four equivalent U(1), two equivalent Ce(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_CeUSi4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.637
_cell_length_b   7.637
_cell_length_c   7.637
_cell_angle_alpha   149.688
_cell_angle_beta   149.688
_cell_angle_gamma   43.399
_symmetry_Int_Tables_number   1
_cell_volume   113.151
_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
  Ce  Ce0  1  0.250  0.750  0.500  1.0
  U  U1  1  0.000  0.000  0.000  1.0
  Si  Si2  1  0.665  0.165  0.500  1.0
  Si  Si3  1  0.581  0.581  0.000  1.0
  Si  Si4  1  0.835  0.335  0.500  1.0
  Si  Si5  1  0.419  0.419  0.000  1.0
[/CIF]
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