The compound described by NbFe4Si crystallizes in the trigonal P-3m1 space group. Nb(1) is bonded in a 16-coordinate geometry to three equivalent Nb(1), three equivalent Fe(1), nine equivalent Fe(3), and one Si(1) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent Nb(1) and six equivalent Fe(3) atoms to form FeNb6Fe6 cuboctahedra that share corners with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(1)Nb6Fe6 cuboctahedra, faces with two equivalent Fe(2)Fe6Si6 cuboctahedra, and faces with eighteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. In the second Fe site, Fe(2) is bonded to six equivalent Fe(3) and six equivalent Si(1) atoms to form FeFe6Si6 cuboctahedra that share corners with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(2)Fe6Si6 cuboctahedra, faces with two equivalent Fe(1)Nb6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. In the third Fe site, Fe(3) is bonded to three equivalent Nb(1), one Fe(1), one Fe(2), four equivalent Fe(3), and three equivalent Si(1) atoms to form FeNb3Fe6Si3 cuboctahedra that share corners with two equivalent Fe(2)Fe6Si6 cuboctahedra, corners with two equivalent Fe(1)Nb6Fe6 cuboctahedra, corners with fourteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, faces with three equivalent Fe(2)Fe6Si6 cuboctahedra, faces with three equivalent Fe(1)Nb6Fe6 cuboctahedra, and faces with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. Si(1) is bonded in a 13-coordinate geometry to one Nb(1), three equivalent Fe(2), and nine equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_NbFe4Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.791
_cell_length_b   4.791
_cell_length_c   7.535
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   149.780
_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
  Nb  Nb0  1  0.333  0.667  0.418  1.0
  Nb  Nb1  1  0.667  0.333  0.582  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.830  0.170  0.243  1.0
  Fe  Fe5  1  0.830  0.660  0.243  1.0
  Fe  Fe6  1  0.340  0.170  0.243  1.0
  Fe  Fe7  1  0.170  0.830  0.757  1.0
  Fe  Fe8  1  0.170  0.340  0.757  1.0
  Fe  Fe9  1  0.660  0.830  0.757  1.0
  Si  Si10  1  0.667  0.333  0.943  1.0
  Si  Si11  1  0.333  0.667  0.057  1.0
[/CIF]
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The compound described by NbFe4Si crystallizes in the trigonal P-3m1 space group. Nb(1) is bonded in a 16-coordinate geometry to three equivalent Nb(1), three equivalent Fe(1), nine equivalent Fe(3), and one Si(1) atom. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent Nb(1) and six equivalent Fe(3) atoms to form FeNb6Fe6 cuboctahedra that share corners with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(1)Nb6Fe6 cuboctahedra, faces with two equivalent Fe(2)Fe6Si6 cuboctahedra, and faces with eighteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. In the second Fe site, Fe(2) is bonded to six equivalent Fe(3) and six equivalent Si(1) atoms to form FeFe6Si6 cuboctahedra that share corners with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(2)Fe6Si6 cuboctahedra, faces with two equivalent Fe(1)Nb6Fe6 cuboctahedra, and faces with eighteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. In the third Fe site, Fe(3) is bonded to three equivalent Nb(1), one Fe(1), one Fe(2), four equivalent Fe(3), and three equivalent Si(1) atoms to form FeNb3Fe6Si3 cuboctahedra that share corners with two equivalent Fe(2)Fe6Si6 cuboctahedra, corners with two equivalent Fe(1)Nb6Fe6 cuboctahedra, corners with fourteen equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, edges with six equivalent Fe(3)Nb3Fe6Si3 cuboctahedra, faces with three equivalent Fe(2)Fe6Si6 cuboctahedra, faces with three equivalent Fe(1)Nb6Fe6 cuboctahedra, and faces with twelve equivalent Fe(3)Nb3Fe6Si3 cuboctahedra. Si(1) is bonded in a 13-coordinate geometry to one Nb(1), three equivalent Fe(2), and nine equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_NbFe4Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.791
_cell_length_b   4.791
_cell_length_c   7.535
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   149.780
_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
  Nb  Nb0  1  0.333  0.667  0.418  1.0
  Nb  Nb1  1  0.667  0.333  0.582  1.0
  Fe  Fe2  1  0.000  0.000  0.500  1.0
  Fe  Fe3  1  0.000  0.000  0.000  1.0
  Fe  Fe4  1  0.830  0.170  0.243  1.0
  Fe  Fe5  1  0.830  0.660  0.243  1.0
  Fe  Fe6  1  0.340  0.170  0.243  1.0
  Fe  Fe7  1  0.170  0.830  0.757  1.0
  Fe  Fe8  1  0.170  0.340  0.757  1.0
  Fe  Fe9  1  0.660  0.830  0.757  1.0
  Si  Si10  1  0.667  0.333  0.943  1.0
  Si  Si11  1  0.333  0.667  0.057  1.0
[/CIF]
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