The material described by UCo10Si2 crystallizes in the orthorhombic Fmmm space group. U(1) is bonded in a 20-coordinate geometry to four equivalent Co(1), four equivalent Co(3), eight equivalent Co(2), and four equivalent Si(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a 10-coordinate geometry to one U(1), one Co(1), two equivalent Co(3), four equivalent Co(2), and two equivalent Si(1) atoms. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent U(1), two equivalent Co(2), two equivalent Co(3), four equivalent Co(1), and two equivalent Si(1) atoms. In the third Co site, Co(3) is bonded to two equivalent U(1), two equivalent Co(3), four equivalent Co(1), and four equivalent Co(2) atoms to form CoU2Co10 cuboctahedra that share corners with four equivalent Si(1)U2Co8Si2 cuboctahedra, corners with six equivalent Co(3)U2Co10 cuboctahedra, edges with four equivalent Si(1)U2Co8Si2 cuboctahedra, faces with two equivalent Co(3)U2Co10 cuboctahedra, and faces with four equivalent Si(1)U2Co8Si2 cuboctahedra. Si(1) is bonded to two equivalent U(1), four equivalent Co(1), four equivalent Co(2), and two equivalent Si(1) atoms to form distorted SiU2Co8Si2 cuboctahedra that share corners with four equivalent Co(3)U2Co10 cuboctahedra, corners with six equivalent Si(1)U2Co8Si2 cuboctahedra, edges with four equivalent Co(3)U2Co10 cuboctahedra, faces with two equivalent Si(1)U2Co8Si2 cuboctahedra, and faces with four equivalent Co(3)U2Co10 cuboctahedra. is represented by the CIF file [CIF]
data_U(Co5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.833
_cell_length_b   6.301
_cell_length_c   6.153
_cell_angle_alpha   98.663
_cell_angle_beta   113.127
_cell_angle_gamma   67.449
_symmetry_Int_Tables_number   1
_cell_volume   159.135
_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
  U  U0  1  0.000  0.000  0.000  1.0
  Co  Co1  1  0.653  0.348  0.654  1.0
  Co  Co2  1  0.347  0.652  0.346  1.0
  Co  Co3  1  0.999  0.348  0.346  1.0
  Co  Co4  1  0.001  0.652  0.654  1.0
  Co  Co5  1  0.727  0.771  0.224  1.0
  Co  Co6  1  0.273  0.229  0.776  1.0
  Co  Co7  1  0.502  0.771  0.776  1.0
  Co  Co8  1  0.498  0.229  0.224  1.0
  Co  Co9  1  0.500  0.000  0.500  1.0
  Co  Co10  1  0.000  0.000  0.500  1.0
  Si  Si11  1  0.500  0.500  0.000  1.0
  Si  Si12  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by UCo10Si2 crystallizes in the orthorhombic Fmmm space group. U(1) is bonded in a 20-coordinate geometry to four equivalent Co(1), four equivalent Co(3), eight equivalent Co(2), and four equivalent Si(1) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded in a 10-coordinate geometry to one U(1), one Co(1), two equivalent Co(3), four equivalent Co(2), and two equivalent Si(1) atoms. In the second Co site, Co(2) is bonded in a 12-coordinate geometry to two equivalent U(1), two equivalent Co(2), two equivalent Co(3), four equivalent Co(1), and two equivalent Si(1) atoms. In the third Co site, Co(3) is bonded to two equivalent U(1), two equivalent Co(3), four equivalent Co(1), and four equivalent Co(2) atoms to form CoU2Co10 cuboctahedra that share corners with four equivalent Si(1)U2Co8Si2 cuboctahedra, corners with six equivalent Co(3)U2Co10 cuboctahedra, edges with four equivalent Si(1)U2Co8Si2 cuboctahedra, faces with two equivalent Co(3)U2Co10 cuboctahedra, and faces with four equivalent Si(1)U2Co8Si2 cuboctahedra. Si(1) is bonded to two equivalent U(1), four equivalent Co(1), four equivalent Co(2), and two equivalent Si(1) atoms to form distorted SiU2Co8Si2 cuboctahedra that share corners with four equivalent Co(3)U2Co10 cuboctahedra, corners with six equivalent Si(1)U2Co8Si2 cuboctahedra, edges with four equivalent Co(3)U2Co10 cuboctahedra, faces with two equivalent Si(1)U2Co8Si2 cuboctahedra, and faces with four equivalent Co(3)U2Co10 cuboctahedra. is represented by the CIF file [CIF]
data_U(Co5Si)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.833
_cell_length_b   6.301
_cell_length_c   6.153
_cell_angle_alpha   98.663
_cell_angle_beta   113.127
_cell_angle_gamma   67.449
_symmetry_Int_Tables_number   1
_cell_volume   159.135
_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
  U  U0  1  0.000  0.000  0.000  1.0
  Co  Co1  1  0.653  0.348  0.654  1.0
  Co  Co2  1  0.347  0.652  0.346  1.0
  Co  Co3  1  0.999  0.348  0.346  1.0
  Co  Co4  1  0.001  0.652  0.654  1.0
  Co  Co5  1  0.727  0.771  0.224  1.0
  Co  Co6  1  0.273  0.229  0.776  1.0
  Co  Co7  1  0.502  0.771  0.776  1.0
  Co  Co8  1  0.498  0.229  0.224  1.0
  Co  Co9  1  0.500  0.000  0.500  1.0
  Co  Co10  1  0.000  0.000  0.500  1.0
  Si  Si11  1  0.500  0.500  0.000  1.0
  Si  Si12  1  0.000  0.500  0.000  1.0
[/CIF]
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