data_U6Fe16Si7C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.21
_cell_length_b   8.21
_cell_length_c   8.21
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   U6Fe16Si7C
_chemical_formula_sum   'U6 Fe16 Si7 C1'
_cell_volume   390.91
_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  0.8  0.8  0.49  1.0
  U  U1  1  0.8  0.12  0.8  1.0
  U  U2  1  0.8  0.8  0.12  1.0
  U  U3  1  0.49  0.8  0.8  1.0
  U  U4  1  0.12  0.8  0.8  1.0
  U  U5  1  0.8  0.49  0.8  1.0
  Fe  Fe6  1  0.23  0.38  0.23  1.0
  Fe  Fe7  1  0.58  0.58  0.58  1.0
  Fe  Fe8  1  0.58  0.83  0.83  1.0
  Fe  Fe9  1  0.03  0.77  0.77  1.0
  Fe  Fe10  1  0.83  0.58  0.83  1.0
  Fe  Fe11  1  0.83  0.83  0.58  1.0
  Fe  Fe12  1  0.77  0.77  0.03  1.0
  Fe  Fe13  1  0.23  0.38  0.38  1.0
  Fe  Fe14  1  0.77  0.03  0.77  1.0
  Fe  Fe15  1  0.23  0.23  0.23  1.0
  Fe  Fe16  1  0.38  0.23  0.23  1.0
  Fe  Fe17  1  0.38  0.23  0.38  1.0
  Fe  Fe18  1  0.38  0.38  0.23  1.0
  Fe  Fe19  1  0.03  0.03  0.03  1.0
  Fe  Fe20  1  0.38  0.38  0.38  1.0
  Fe  Fe21  1  0.23  0.23  0.38  1.0
  Si  Si22  1  0.9  0.9  0.8  1.0
  Si  Si23  1  0.8  0.8  0.8  1.0
  Si  Si24  1  0.9  0.8  0.9  1.0
  Si  Si25  1  0.9  0.9  0.0  1.0
  Si  Si26  1  0.8  0.9  0.9  1.0
  Si  Si27  1  0.9  0.0  0.9  1.0
  Si  Si28  1  0.0  0.9  0.9  1.0
  C  C29  1  0.0  0.0  0.0  1.0

data_U6Fe16Si7C
_symmetry_space_group_name_H-M   R3m
_cell_length_a   8.21
_cell_length_b   8.21
_cell_length_c   20.1
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   U6Fe16Si7C
_chemical_formula_sum   'U18 Fe48 Si21 C3'
_cell_volume   1172.72
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  9  0.11  0.21  0.09  1.0
  U  U1  9  0.21  0.11  0.3  1.0
  Fe  Fe2  9  0.05  0.1  0.72  1.0
  Fe  Fe3  9  0.09  0.17  0.14  1.0
  Fe  Fe4  9  0.1  0.05  0.67  1.0
  Fe  Fe5  9  0.17  0.09  0.25  1.0
  Fe  Fe6  3  0.0  0.0  0.42  1.0
  Fe  Fe7  3  0.0  0.0  0.62  1.0
  Fe  Fe8  3  0.0  0.0  0.77  1.0
  Fe  Fe9  3  0.0  0.0  0.97  1.0
  Si  Si10  9  0.03  0.07  0.07  1.0
  Si  Si11  9  0.07  0.03  0.13  1.0
  Si  Si12  3  0.0  0.0  0.2  1.0
  C  C13  3  0.0  0.0  0.0  1.0

U U U U U U Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Si Si Si Si Si Si Si C
U U U U U U Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Fe Si Si Si Si Si Si Si C 0 11 o o o 0 7 o o o 1 14 o o o 1 27 o o o 1 7 o o o 2 12 o o o 2 25 o o o 2 7 o o o 3 8 o o o 3 7 o o o 4 9 o o o 4 28 o o o 4 7 o o o 5 10 o o o 5 7 o o o 6 15 o o o 6 21 o o o 6 16 o o o 6 18 o o o 6 13 o o o 8 23 o o o 9 24 - o o 9 22 - o o 9 23 - o o 10 23 o o o 11 23 o o o 12 26 o o - 12 24 o o - 12 23 o o - 13 21 o o o 13 17 o o o 13 18 o o o 13 20 o o o 14 26 o - o 14 22 o - o 14 23 o - o 15 21 o o o 15 16 o o o 16 21 o o o 16 18 o o o 16 17 o o o 17 21 o o o 17 18 o o o 17 20 o o o 18 20 o o o 19 29 o o o 22 24 o o o 22 26 o o o 22 23 o o o 23 26 o o o 23 24 o o o 24 26 o o o 25 28 + o - 25 27 o + - 27 28 + - o 
U6Fe16Si7C crystallizes in the trigonal R3m space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a single-bond geometry to one Fe(2), one Fe(3), and two equivalent Fe(5) atoms. The U(1)-Fe(2) bond length is 2.86 Å. The U(1)-Fe(3) bond length is 1.04 Å. Both U(1)-Fe(5) bond lengths are 3.57 Å. In the second U site, U(2) is bonded in a water-like geometry to one Fe(2), one Fe(4), and one Si(3) atom. The U(2)-Fe(2) bond length is 3.24 Å. The U(2)-Fe(4) bond length is 1.04 Å. The U(2)-Si(3) bond length is 1.15 Å. There are eight inequivalent Fe sites. In the first Fe site, Fe(8) is bonded in a 3-coordinate geometry to three equivalent Fe(5) atoms. All Fe(8)-Fe(5) bond lengths are 1.28 Å. In the second Fe site, Fe(1) is bonded in a 5-coordinate geometry to one Fe(6), two equivalent Fe(1), and two equivalent Fe(5) atoms. The Fe(1)-Fe(6) bond length is 1.28 Å. Both Fe(1)-Fe(1) bond lengths are 1.28 Å. Both Fe(1)-Fe(5) bond lengths are 1.28 Å. In the third Fe site, Fe(2) is bonded in a 6-coordinate geometry to three equivalent U(1) and three equivalent U(2) atoms. In the fourth Fe site, Fe(3) is bonded in a distorted bent 150 degrees geometry to one U(1) and one Si(2) atom. The Fe(3)-Si(2) bond length is 1.65 Å. In the fifth Fe site, Fe(4) is bonded in a 3-coordinate geometry to one U(2), one Si(2), and two equivalent Si(1) atoms. The Fe(4)-Si(2) bond length is 1.65 Å. Both Fe(4)-Si(1) bond lengths are 1.08 Å. In the sixth Fe site, Fe(5) is bonded in a 7-coordinate geometry to two equivalent U(1), one Fe(8), two equivalent Fe(1), and two equivalent Fe(5) atoms. Both Fe(5)-Fe(5) bond lengths are 1.28 Å. In the seventh Fe site, Fe(6) is bonded in a 3-coordinate geometry to three equivalent Fe(1) atoms. In the eighth Fe site, Fe(7) is bonded in a single-bond geometry to one C(1) atom. The Fe(7)-C(1) bond length is 0.60 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 2-coordinate geometry to two equivalent Fe(4), one Si(2), and two equivalent Si(1) atoms. The Si(1)-Si(2) bond length is 1.40 Å. Both Si(1)-Si(1) bond lengths are 0.81 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Fe(3), three equivalent Fe(4), and three equivalent Si(1) atoms. In the third Si site, Si(3) is bonded in a 4-coordinate geometry to one U(2), two equivalent Si(3), and one C(1) atom. Both Si(3)-Si(3) bond lengths are 0.81 Å. The Si(3)-C(1) bond length is 1.40 Å. C(1) is bonded in a distorted single-bond geometry to one Fe(7) and three equivalent Si(3) atoms.