The compound described by Gd2Fe17C crystallizes in the monoclinic C2/m space group. Gd(1) is bonded in a distorted single-bond geometry to one Fe(1), one Fe(6), two equivalent Fe(7), four equivalent Fe(5), six equivalent Fe(3), and one C(1) atom. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Gd(1), one Fe(1), one Fe(2), one Fe(6), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(7), and four equivalent Fe(5) atoms. In the second Fe site, Fe(2) is bonded in a single-bond geometry to one Fe(1), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(7), and one C(1) atom. In the third Fe site, Fe(3) is bonded to three equivalent Gd(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(6), one Fe(7), and three equivalent Fe(5) atoms to form FeGd3Fe9 cuboctahedra that share  a cornercorner with one Fe(6)Gd2Fe10 cuboctahedra, corners with four equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with seven equivalent Fe(3)Gd3Fe9 cuboctahedra, corners with two equivalent C(1)Gd2Fe4 octahedra,  an edgeedge with one Fe(6)Gd2Fe10 cuboctahedra, edges with two equivalent Fe(7)Gd2Fe10 cuboctahedra, edges with three equivalent Fe(3)Gd3Fe9 cuboctahedra,  a faceface with one Fe(6)Gd2Fe10 cuboctahedra, faces with two equivalent Fe(7)Gd2Fe10 cuboctahedra, faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra, and  a faceface with one C(1)Gd2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-70°. In the fourth Fe site, Fe(4) is bonded in a single-bond geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(7), and one C(1) atom. In the fifth Fe site, Fe(5) is bonded in a 12-coordinate geometry to two equivalent Gd(1), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(1), and three equivalent Fe(3) atoms. In the sixth Fe site, Fe(6) is bonded to two equivalent Gd(1), two equivalent Fe(1), four equivalent Fe(3), and four equivalent Fe(5) atoms to form FeGd2Fe10 cuboctahedra that share corners with four equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with four equivalent Fe(3)Gd3Fe9 cuboctahedra, corners with two equivalent C(1)Gd2Fe4 octahedra, edges with four equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with four equivalent Fe(7)Gd2Fe10 cuboctahedra, and faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 46°. In the seventh Fe site, Fe(7) is bonded to two equivalent Gd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Fe(5) atoms to form distorted FeGd2Fe10 cuboctahedra that share corners with two equivalent Fe(6)Gd2Fe10 cuboctahedra, corners with two equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Gd3Fe9 cuboctahedra, edges with four equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with two equivalent Fe(6)Gd2Fe10 cuboctahedra, faces with two equivalent Fe(7)Gd2Fe10 cuboctahedra, faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra, and faces with two equivalent C(1)Gd2Fe4 octahedra. C(1) is bonded to two equivalent Gd(1), two equivalent Fe(2), and two equivalent Fe(4) atoms to form CGd2Fe4 octahedra that share corners with two equivalent Fe(6)Gd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with four equivalent Fe(7)Gd2Fe10 cuboctahedra, and faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra. is represented by the CIF card [CIF]
data_Gd2Fe17C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.371
_cell_length_b   6.323
_cell_length_c   6.371
_cell_angle_alpha   83.312
_cell_angle_beta   83.397
_cell_angle_gamma   83.312
_symmetry_Int_Tables_number   1
_cell_volume   251.856
_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
  Gd  Gd0  1  0.657  0.648  0.657  1.0
  Gd  Gd1  1  0.343  0.352  0.343  1.0
  Fe  Fe2  1  0.903  0.902  0.903  1.0
  Fe  Fe3  1  0.097  0.098  0.097  1.0
  Fe  Fe4  1  0.346  0.850  0.346  1.0
  Fe  Fe5  1  0.852  0.349  0.343  1.0
  Fe  Fe6  1  0.343  0.349  0.852  1.0
  Fe  Fe7  1  0.654  0.150  0.654  1.0
  Fe  Fe8  1  0.148  0.651  0.657  1.0
  Fe  Fe9  1  0.657  0.651  0.148  1.0
  Fe  Fe10  1  0.719  0.000  0.281  1.0
  Fe  Fe11  1  0.997  0.285  0.714  1.0
  Fe  Fe12  1  0.286  0.715  0.003  1.0
  Fe  Fe13  1  0.003  0.715  0.286  1.0
  Fe  Fe14  1  0.714  0.285  0.997  1.0
  Fe  Fe15  1  0.281  0.000  0.719  1.0
  Fe  Fe16  1  0.000  0.500  0.000  1.0
  Fe  Fe17  1  0.500  0.000  0.000  1.0
  Fe  Fe18  1  0.000  0.000  0.500  1.0
  C  C19  1  0.500  0.000  0.500  1.0
[/CIF]
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The compound described by Gd2Fe17C crystallizes in the monoclinic C2/m space group. Gd(1) is bonded in a distorted single-bond geometry to one Fe(1), one Fe(6), two equivalent Fe(7), four equivalent Fe(5), six equivalent Fe(3), and one C(1) atom. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 14-coordinate geometry to one Gd(1), one Fe(1), one Fe(2), one Fe(6), two equivalent Fe(3), two equivalent Fe(4), two equivalent Fe(7), and four equivalent Fe(5) atoms. In the second Fe site, Fe(2) is bonded in a single-bond geometry to one Fe(1), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(7), and one C(1) atom. In the third Fe site, Fe(3) is bonded to three equivalent Gd(1), one Fe(1), one Fe(2), one Fe(3), one Fe(4), one Fe(6), one Fe(7), and three equivalent Fe(5) atoms to form FeGd3Fe9 cuboctahedra that share  a cornercorner with one Fe(6)Gd2Fe10 cuboctahedra, corners with four equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with seven equivalent Fe(3)Gd3Fe9 cuboctahedra, corners with two equivalent C(1)Gd2Fe4 octahedra,  an edgeedge with one Fe(6)Gd2Fe10 cuboctahedra, edges with two equivalent Fe(7)Gd2Fe10 cuboctahedra, edges with three equivalent Fe(3)Gd3Fe9 cuboctahedra,  a faceface with one Fe(6)Gd2Fe10 cuboctahedra, faces with two equivalent Fe(7)Gd2Fe10 cuboctahedra, faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra, and  a faceface with one C(1)Gd2Fe4 octahedra. The corner-sharing octahedral tilt angles range from 65-70°. In the fourth Fe site, Fe(4) is bonded in a single-bond geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(5), two equivalent Fe(7), and one C(1) atom. In the fifth Fe site, Fe(5) is bonded in a 12-coordinate geometry to two equivalent Gd(1), one Fe(2), one Fe(4), one Fe(5), one Fe(6), one Fe(7), two equivalent Fe(1), and three equivalent Fe(3) atoms. In the sixth Fe site, Fe(6) is bonded to two equivalent Gd(1), two equivalent Fe(1), four equivalent Fe(3), and four equivalent Fe(5) atoms to form FeGd2Fe10 cuboctahedra that share corners with four equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with four equivalent Fe(3)Gd3Fe9 cuboctahedra, corners with two equivalent C(1)Gd2Fe4 octahedra, edges with four equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with four equivalent Fe(7)Gd2Fe10 cuboctahedra, and faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 46°. In the seventh Fe site, Fe(7) is bonded to two equivalent Gd(1), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), and two equivalent Fe(5) atoms to form distorted FeGd2Fe10 cuboctahedra that share corners with two equivalent Fe(6)Gd2Fe10 cuboctahedra, corners with two equivalent Fe(7)Gd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Gd3Fe9 cuboctahedra, edges with four equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with two equivalent Fe(6)Gd2Fe10 cuboctahedra, faces with two equivalent Fe(7)Gd2Fe10 cuboctahedra, faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra, and faces with two equivalent C(1)Gd2Fe4 octahedra. C(1) is bonded to two equivalent Gd(1), two equivalent Fe(2), and two equivalent Fe(4) atoms to form CGd2Fe4 octahedra that share corners with two equivalent Fe(6)Gd2Fe10 cuboctahedra, corners with eight equivalent Fe(3)Gd3Fe9 cuboctahedra, faces with four equivalent Fe(7)Gd2Fe10 cuboctahedra, and faces with four equivalent Fe(3)Gd3Fe9 cuboctahedra. is represented by the CIF card [CIF]
data_Gd2Fe17C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.371
_cell_length_b   6.323
_cell_length_c   6.371
_cell_angle_alpha   83.312
_cell_angle_beta   83.397
_cell_angle_gamma   83.312
_symmetry_Int_Tables_number   1
_cell_volume   251.856
_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
  Gd  Gd0  1  0.657  0.648  0.657  1.0
  Gd  Gd1  1  0.343  0.352  0.343  1.0
  Fe  Fe2  1  0.903  0.902  0.903  1.0
  Fe  Fe3  1  0.097  0.098  0.097  1.0
  Fe  Fe4  1  0.346  0.850  0.346  1.0
  Fe  Fe5  1  0.852  0.349  0.343  1.0
  Fe  Fe6  1  0.343  0.349  0.852  1.0
  Fe  Fe7  1  0.654  0.150  0.654  1.0
  Fe  Fe8  1  0.148  0.651  0.657  1.0
  Fe  Fe9  1  0.657  0.651  0.148  1.0
  Fe  Fe10  1  0.719  0.000  0.281  1.0
  Fe  Fe11  1  0.997  0.285  0.714  1.0
  Fe  Fe12  1  0.286  0.715  0.003  1.0
  Fe  Fe13  1  0.003  0.715  0.286  1.0
  Fe  Fe14  1  0.714  0.285  0.997  1.0
  Fe  Fe15  1  0.281  0.000  0.719  1.0
  Fe  Fe16  1  0.000  0.500  0.000  1.0
  Fe  Fe17  1  0.500  0.000  0.000  1.0
  Fe  Fe18  1  0.000  0.000  0.500  1.0
  C  C19  1  0.500  0.000  0.500  1.0
[/CIF]
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