The crystal structure described by Y4C7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one C(2), one C(3), two equivalent C(1), and three equivalent C(4) atoms to form distorted YC7 octahedra that share corners with two equivalent Y(1)C7 octahedra,  a cornercorner with one C(2)Y4C trigonal bipyramid, and edges with five equivalent Y(1)C7 octahedra. The corner-sharing octahedra are not tilted. In the second Y site, Y(2) is bonded in a 9-coordinate geometry to one C(1), two equivalent C(4), three equivalent C(2), and three equivalent C(3) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Y(2) and four equivalent Y(1) atoms to form CY6 octahedra that share corners with two equivalent C(2)Y4C trigonal bipyramids, edges with two equivalent C(1)Y6 octahedra, and edges with four equivalent C(2)Y4C trigonal bipyramids. In the second C site, C(2) is bonded to one Y(1), three equivalent Y(2), and one C(3) atom to form distorted CY4C trigonal bipyramids that share  a cornercorner with one Y(1)C7 octahedra,  a cornercorner with one C(1)Y6 octahedra, corners with six equivalent C(2)Y4C trigonal bipyramids, and edges with two equivalent C(1)Y6 octahedra. The corner-sharing octahedral tilt angles range from 33-61°. In the third C site, C(3) is bonded in a 6-coordinate geometry to one Y(1), three equivalent Y(2), one C(2), and one C(4) atom. In the fourth C site, C(4) is bonded in a 5-coordinate geometry to two equivalent Y(2), three equivalent Y(1), and one C(3) atom. is represented by the CIF file [CIF]
data_Y4C7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.710
_cell_length_b   6.467
_cell_length_c   13.712
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   104.636
_symmetry_Int_Tables_number   1
_cell_volume   318.316
_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
  Y  Y0  1  0.633  0.260  0.945  1.0
  Y  Y1  1  0.367  0.240  0.445  1.0
  Y  Y2  1  0.367  0.740  0.055  1.0
  Y  Y3  1  0.633  0.760  0.555  1.0
  Y  Y4  1  0.945  0.339  0.663  1.0
  Y  Y5  1  0.055  0.161  0.163  1.0
  Y  Y6  1  0.055  0.661  0.337  1.0
  Y  Y7  1  0.945  0.839  0.837  1.0
  C  C8  1  0.000  0.500  0.500  1.0
  C  C9  1  0.000  0.000  0.000  1.0
  C  C10  1  0.532  0.076  0.784  1.0
  C  C11  1  0.468  0.424  0.284  1.0
  C  C12  1  0.468  0.924  0.216  1.0
  C  C13  1  0.532  0.576  0.716  1.0
  C  C14  1  0.620  0.453  0.196  1.0
  C  C15  1  0.380  0.047  0.696  1.0
  C  C16  1  0.733  0.951  0.395  1.0
  C  C17  1  0.267  0.549  0.895  1.0
  C  C18  1  0.267  0.049  0.605  1.0
  C  C19  1  0.733  0.451  0.105  1.0
  C  C20  1  0.620  0.953  0.304  1.0
  C  C21  1  0.380  0.547  0.804  1.0
[/CIF]
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The crystal structure described by Y4C7 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one C(2), one C(3), two equivalent C(1), and three equivalent C(4) atoms to form distorted YC7 octahedra that share corners with two equivalent Y(1)C7 octahedra,  a cornercorner with one C(2)Y4C trigonal bipyramid, and edges with five equivalent Y(1)C7 octahedra. The corner-sharing octahedra are not tilted. In the second Y site, Y(2) is bonded in a 9-coordinate geometry to one C(1), two equivalent C(4), three equivalent C(2), and three equivalent C(3) atoms. There are four inequivalent C sites. In the first C site, C(1) is bonded to two equivalent Y(2) and four equivalent Y(1) atoms to form CY6 octahedra that share corners with two equivalent C(2)Y4C trigonal bipyramids, edges with two equivalent C(1)Y6 octahedra, and edges with four equivalent C(2)Y4C trigonal bipyramids. In the second C site, C(2) is bonded to one Y(1), three equivalent Y(2), and one C(3) atom to form distorted CY4C trigonal bipyramids that share  a cornercorner with one Y(1)C7 octahedra,  a cornercorner with one C(1)Y6 octahedra, corners with six equivalent C(2)Y4C trigonal bipyramids, and edges with two equivalent C(1)Y6 octahedra. The corner-sharing octahedral tilt angles range from 33-61°. In the third C site, C(3) is bonded in a 6-coordinate geometry to one Y(1), three equivalent Y(2), one C(2), and one C(4) atom. In the fourth C site, C(4) is bonded in a 5-coordinate geometry to two equivalent Y(2), three equivalent Y(1), and one C(3) atom. is represented by the CIF file [CIF]
data_Y4C7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.710
_cell_length_b   6.467
_cell_length_c   13.712
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   104.636
_symmetry_Int_Tables_number   1
_cell_volume   318.316
_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
  Y  Y0  1  0.633  0.260  0.945  1.0
  Y  Y1  1  0.367  0.240  0.445  1.0
  Y  Y2  1  0.367  0.740  0.055  1.0
  Y  Y3  1  0.633  0.760  0.555  1.0
  Y  Y4  1  0.945  0.339  0.663  1.0
  Y  Y5  1  0.055  0.161  0.163  1.0
  Y  Y6  1  0.055  0.661  0.337  1.0
  Y  Y7  1  0.945  0.839  0.837  1.0
  C  C8  1  0.000  0.500  0.500  1.0
  C  C9  1  0.000  0.000  0.000  1.0
  C  C10  1  0.532  0.076  0.784  1.0
  C  C11  1  0.468  0.424  0.284  1.0
  C  C12  1  0.468  0.924  0.216  1.0
  C  C13  1  0.532  0.576  0.716  1.0
  C  C14  1  0.620  0.453  0.196  1.0
  C  C15  1  0.380  0.047  0.696  1.0
  C  C16  1  0.733  0.951  0.395  1.0
  C  C17  1  0.267  0.549  0.895  1.0
  C  C18  1  0.267  0.049  0.605  1.0
  C  C19  1  0.733  0.451  0.105  1.0
  C  C20  1  0.620  0.953  0.304  1.0
  C  C21  1  0.380  0.547  0.804  1.0
[/CIF]
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