The material described by Y2Co17C crystallizes in the monoclinic C2/m space group. Y(1) is bonded in a distorted single-bond geometry to one Co(1), one Co(6), two equivalent Co(7), four equivalent Co(5), six equivalent Co(3), and one C(1) atom. There are seven inequivalent Co sites. In the first Co site, Co(1) is bonded in a 14-coordinate geometry to one Y(1), one Co(1), one Co(2), one Co(6), two equivalent Co(3), two equivalent Co(4), two equivalent Co(7), and four equivalent Co(5) atoms. In the second Co site, Co(2) is bonded in a single-bond geometry to one Co(1), two equivalent Co(3), two equivalent Co(5), two equivalent Co(7), and one C(1) atom. In the third Co site, Co(3) is bonded to three equivalent Y(1), one Co(1), one Co(2), one Co(3), one Co(4), one Co(6), one Co(7), and three equivalent Co(5) atoms to form distorted CoY3Co9 cuboctahedra that share  a cornercorner with one Co(6)Y2Co10 cuboctahedra, corners with four equivalent Co(7)Y2Co10 cuboctahedra, corners with five equivalent Co(5)Y2Co10 cuboctahedra, corners with seven equivalent Co(3)Y3Co9 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra,  an edgeedge with one Co(5)Y2Co10 cuboctahedra,  an edgeedge with one Co(6)Y2Co10 cuboctahedra, edges with two equivalent Co(7)Y2Co10 cuboctahedra, edges with three equivalent Co(3)Y3Co9 cuboctahedra,  a faceface with one Co(6)Y2Co10 cuboctahedra, faces with two equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(3)Y3Co9 cuboctahedra, faces with seven equivalent Co(5)Y2Co10 cuboctahedra, and  a faceface with one C(1)Y2Co4 octahedra. The corner-sharing octahedral tilt angles range from 66-70°. In the fourth Co site, Co(4) is bonded in a single-bond geometry to two equivalent Co(1), two equivalent Co(3), two equivalent Co(5), two equivalent Co(7), and one C(1) atom. In the fifth Co site, Co(5) is bonded to two equivalent Y(1), one Co(2), one Co(4), one Co(5), one Co(6), one Co(7), two equivalent Co(1), and three equivalent Co(3) atoms to form distorted CoY2Co10 cuboctahedra that share  a cornercorner with one Co(6)Y2Co10 cuboctahedra, corners with three equivalent Co(7)Y2Co10 cuboctahedra, corners with five equivalent Co(3)Y3Co9 cuboctahedra, corners with seven equivalent Co(5)Y2Co10 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra,  an edgeedge with one Co(5)Y2Co10 cuboctahedra,  an edgeedge with one Co(6)Y2Co10 cuboctahedra,  an edgeedge with one Co(7)Y2Co10 cuboctahedra,  an edgeedge with one Co(3)Y3Co9 cuboctahedra,  an edgeedge with one C(1)Y2Co4 octahedra,  a faceface with one Co(6)Y2Co10 cuboctahedra, faces with three equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(5)Y2Co10 cuboctahedra, and faces with seven equivalent Co(3)Y3Co9 cuboctahedra. The corner-sharing octahedral tilt angles range from 25-29°. In the sixth Co site, Co(6) is bonded to two equivalent Y(1), two equivalent Co(1), four equivalent Co(3), and four equivalent Co(5) atoms to form CoY2Co10 cuboctahedra that share corners with four equivalent Co(5)Y2Co10 cuboctahedra, corners with four equivalent Co(7)Y2Co10 cuboctahedra, corners with four equivalent Co(3)Y3Co9 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra, edges with four equivalent Co(5)Y2Co10 cuboctahedra, edges with four equivalent Co(3)Y3Co9 cuboctahedra, faces with four equivalent Co(5)Y2Co10 cuboctahedra, faces with four equivalent Co(7)Y2Co10 cuboctahedra, and faces with four equivalent Co(3)Y3Co9 cuboctahedra. The corner-sharing octahedral tilt angles are 46°. In the seventh Co site, Co(7) is bonded to two equivalent Y(1), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), two equivalent Co(4), and two equivalent Co(5) atoms to form distorted CoY2Co10 cuboctahedra that share corners with two equivalent Co(6)Y2Co10 cuboctahedra, corners with two equivalent Co(7)Y2Co10 cuboctahedra, corners with six equivalent Co(5)Y2Co10 cuboctahedra, corners with eight equivalent Co(3)Y3Co9 cuboctahedra, edges with two equivalent Co(5)Y2Co10 cuboctahedra, edges with four equivalent Co(3)Y3Co9 cuboctahedra, faces with two equivalent Co(6)Y2Co10 cuboctahedra, faces with two equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(3)Y3Co9 cuboctahedra, faces with six equivalent Co(5)Y2Co10 cuboctahedra, and faces with two equivalent C(1)Y2Co4 octahedra. C(1) is bonded to two equivalent Y(1), two equivalent Co(2), and two equivalent Co(4) atoms to form CY2Co4 octahedra that share corners with two equivalent Co(6)Y2Co10 cuboctahedra, corners with eight equivalent Co(5)Y2Co10 cuboctahedra, corners with eight equivalent Co(3)Y3Co9 cuboctahedra, edges with four equivalent Co(5)Y2Co10 cuboctahedra, faces with four equivalent Co(7)Y2Co10 cuboctahedra, and faces with four equivalent Co(3)Y3Co9 cuboctahedra. is represented by the CIF card [CIF]
data_Y2Co17C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.332
_cell_length_b   6.279
_cell_length_c   6.332
_cell_angle_alpha   83.436
_cell_angle_beta   83.450
_cell_angle_gamma   83.436
_symmetry_Int_Tables_number   1
_cell_volume   247.163
_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
  Y  Y0  1  0.660  0.646  0.660  1.0
  Y  Y1  1  0.340  0.354  0.340  1.0
  Co  Co2  1  0.904  0.902  0.904  1.0
  Co  Co3  1  0.096  0.098  0.096  1.0
  Co  Co4  1  0.346  0.853  0.346  1.0
  Co  Co5  1  0.858  0.350  0.345  1.0
  Co  Co6  1  0.345  0.350  0.858  1.0
  Co  Co7  1  0.654  0.147  0.654  1.0
  Co  Co8  1  0.142  0.650  0.655  1.0
  Co  Co9  1  0.655  0.650  0.142  1.0
  Co  Co10  1  0.718  0.000  0.282  1.0
  Co  Co11  1  0.999  0.287  0.715  1.0
  Co  Co12  1  0.285  0.713  0.001  1.0
  Co  Co13  1  0.001  0.713  0.285  1.0
  Co  Co14  1  0.715  0.287  0.999  1.0
  Co  Co15  1  0.282  0.000  0.718  1.0
  Co  Co16  1  0.000  0.500  0.000  1.0
  Co  Co17  1  0.500  0.000  0.000  1.0
  Co  Co18  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 material described by Y2Co17C crystallizes in the monoclinic C2/m space group. Y(1) is bonded in a distorted single-bond geometry to one Co(1), one Co(6), two equivalent Co(7), four equivalent Co(5), six equivalent Co(3), and one C(1) atom. There are seven inequivalent Co sites. In the first Co site, Co(1) is bonded in a 14-coordinate geometry to one Y(1), one Co(1), one Co(2), one Co(6), two equivalent Co(3), two equivalent Co(4), two equivalent Co(7), and four equivalent Co(5) atoms. In the second Co site, Co(2) is bonded in a single-bond geometry to one Co(1), two equivalent Co(3), two equivalent Co(5), two equivalent Co(7), and one C(1) atom. In the third Co site, Co(3) is bonded to three equivalent Y(1), one Co(1), one Co(2), one Co(3), one Co(4), one Co(6), one Co(7), and three equivalent Co(5) atoms to form distorted CoY3Co9 cuboctahedra that share  a cornercorner with one Co(6)Y2Co10 cuboctahedra, corners with four equivalent Co(7)Y2Co10 cuboctahedra, corners with five equivalent Co(5)Y2Co10 cuboctahedra, corners with seven equivalent Co(3)Y3Co9 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra,  an edgeedge with one Co(5)Y2Co10 cuboctahedra,  an edgeedge with one Co(6)Y2Co10 cuboctahedra, edges with two equivalent Co(7)Y2Co10 cuboctahedra, edges with three equivalent Co(3)Y3Co9 cuboctahedra,  a faceface with one Co(6)Y2Co10 cuboctahedra, faces with two equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(3)Y3Co9 cuboctahedra, faces with seven equivalent Co(5)Y2Co10 cuboctahedra, and  a faceface with one C(1)Y2Co4 octahedra. The corner-sharing octahedral tilt angles range from 66-70°. In the fourth Co site, Co(4) is bonded in a single-bond geometry to two equivalent Co(1), two equivalent Co(3), two equivalent Co(5), two equivalent Co(7), and one C(1) atom. In the fifth Co site, Co(5) is bonded to two equivalent Y(1), one Co(2), one Co(4), one Co(5), one Co(6), one Co(7), two equivalent Co(1), and three equivalent Co(3) atoms to form distorted CoY2Co10 cuboctahedra that share  a cornercorner with one Co(6)Y2Co10 cuboctahedra, corners with three equivalent Co(7)Y2Co10 cuboctahedra, corners with five equivalent Co(3)Y3Co9 cuboctahedra, corners with seven equivalent Co(5)Y2Co10 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra,  an edgeedge with one Co(5)Y2Co10 cuboctahedra,  an edgeedge with one Co(6)Y2Co10 cuboctahedra,  an edgeedge with one Co(7)Y2Co10 cuboctahedra,  an edgeedge with one Co(3)Y3Co9 cuboctahedra,  an edgeedge with one C(1)Y2Co4 octahedra,  a faceface with one Co(6)Y2Co10 cuboctahedra, faces with three equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(5)Y2Co10 cuboctahedra, and faces with seven equivalent Co(3)Y3Co9 cuboctahedra. The corner-sharing octahedral tilt angles range from 25-29°. In the sixth Co site, Co(6) is bonded to two equivalent Y(1), two equivalent Co(1), four equivalent Co(3), and four equivalent Co(5) atoms to form CoY2Co10 cuboctahedra that share corners with four equivalent Co(5)Y2Co10 cuboctahedra, corners with four equivalent Co(7)Y2Co10 cuboctahedra, corners with four equivalent Co(3)Y3Co9 cuboctahedra, corners with two equivalent C(1)Y2Co4 octahedra, edges with four equivalent Co(5)Y2Co10 cuboctahedra, edges with four equivalent Co(3)Y3Co9 cuboctahedra, faces with four equivalent Co(5)Y2Co10 cuboctahedra, faces with four equivalent Co(7)Y2Co10 cuboctahedra, and faces with four equivalent Co(3)Y3Co9 cuboctahedra. The corner-sharing octahedral tilt angles are 46°. In the seventh Co site, Co(7) is bonded to two equivalent Y(1), two equivalent Co(1), two equivalent Co(2), two equivalent Co(3), two equivalent Co(4), and two equivalent Co(5) atoms to form distorted CoY2Co10 cuboctahedra that share corners with two equivalent Co(6)Y2Co10 cuboctahedra, corners with two equivalent Co(7)Y2Co10 cuboctahedra, corners with six equivalent Co(5)Y2Co10 cuboctahedra, corners with eight equivalent Co(3)Y3Co9 cuboctahedra, edges with two equivalent Co(5)Y2Co10 cuboctahedra, edges with four equivalent Co(3)Y3Co9 cuboctahedra, faces with two equivalent Co(6)Y2Co10 cuboctahedra, faces with two equivalent Co(7)Y2Co10 cuboctahedra, faces with four equivalent Co(3)Y3Co9 cuboctahedra, faces with six equivalent Co(5)Y2Co10 cuboctahedra, and faces with two equivalent C(1)Y2Co4 octahedra. C(1) is bonded to two equivalent Y(1), two equivalent Co(2), and two equivalent Co(4) atoms to form CY2Co4 octahedra that share corners with two equivalent Co(6)Y2Co10 cuboctahedra, corners with eight equivalent Co(5)Y2Co10 cuboctahedra, corners with eight equivalent Co(3)Y3Co9 cuboctahedra, edges with four equivalent Co(5)Y2Co10 cuboctahedra, faces with four equivalent Co(7)Y2Co10 cuboctahedra, and faces with four equivalent Co(3)Y3Co9 cuboctahedra. is represented by the CIF card [CIF]
data_Y2Co17C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.332
_cell_length_b   6.279
_cell_length_c   6.332
_cell_angle_alpha   83.436
_cell_angle_beta   83.450
_cell_angle_gamma   83.436
_symmetry_Int_Tables_number   1
_cell_volume   247.163
_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
  Y  Y0  1  0.660  0.646  0.660  1.0
  Y  Y1  1  0.340  0.354  0.340  1.0
  Co  Co2  1  0.904  0.902  0.904  1.0
  Co  Co3  1  0.096  0.098  0.096  1.0
  Co  Co4  1  0.346  0.853  0.346  1.0
  Co  Co5  1  0.858  0.350  0.345  1.0
  Co  Co6  1  0.345  0.350  0.858  1.0
  Co  Co7  1  0.654  0.147  0.654  1.0
  Co  Co8  1  0.142  0.650  0.655  1.0
  Co  Co9  1  0.655  0.650  0.142  1.0
  Co  Co10  1  0.718  0.000  0.282  1.0
  Co  Co11  1  0.999  0.287  0.715  1.0
  Co  Co12  1  0.285  0.713  0.001  1.0
  Co  Co13  1  0.001  0.713  0.285  1.0
  Co  Co14  1  0.715  0.287  0.999  1.0
  Co  Co15  1  0.282  0.000  0.718  1.0
  Co  Co16  1  0.000  0.500  0.000  1.0
  Co  Co17  1  0.500  0.000  0.000  1.0
  Co  Co18  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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