The compound described by HoMoC2 crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to three equivalent C(2) and four equivalent C(1) atoms to form distorted HoC7 pentagonal bipyramids that share corners with four equivalent Ho(1)C7 pentagonal bipyramids, corners with three equivalent Mo(1)C5 trigonal bipyramids, edges with four equivalent Ho(1)C7 pentagonal bipyramids, edges with seven equivalent Mo(1)C5 trigonal bipyramids, and faces with two equivalent Ho(1)C7 pentagonal bipyramids. Mo(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form MoC5 trigonal bipyramids that share corners with three equivalent Ho(1)C7 pentagonal bipyramids, corners with four equivalent Mo(1)C5 trigonal bipyramids, edges with seven equivalent Ho(1)C7 pentagonal bipyramids, and edges with two equivalent Mo(1)C5 trigonal bipyramids. There are two inequivalent C sites. In the first C site, C(1) is bonded to four equivalent Ho(1) and two equivalent Mo(1) atoms to form CHo4Mo2 octahedra that share corners with four equivalent C(1)Ho4Mo2 octahedra, corners with nine equivalent C(2)Ho3Mo3 octahedra, edges with two equivalent C(1)Ho4Mo2 octahedra, edges with three equivalent C(2)Ho3Mo3 octahedra,  a faceface with one C(2)Ho3Mo3 octahedra, and faces with two equivalent C(1)Ho4Mo2 octahedra. The corner-sharing octahedral tilt angles range from 11-60°. In the second C site, C(2) is bonded to three equivalent Ho(1) and three equivalent Mo(1) atoms to form CHo3Mo3 octahedra that share corners with nine equivalent C(1)Ho4Mo2 octahedra, edges with three equivalent C(1)Ho4Mo2 octahedra, edges with six equivalent C(2)Ho3Mo3 octahedra, and  a faceface with one C(1)Ho4Mo2 octahedra. The corner-sharing octahedral tilt angles range from 11-60°. is represented by the CIF file [CIF]
data_HoMoC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.379
_cell_length_b   5.691
_cell_length_c   10.775
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   207.204
_cell_formula_units_Z   4
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
  Ho  Ho0  1  0.250  0.085  0.863  1.0
  Ho  Ho1  1  0.250  0.585  0.637  1.0
  Ho  Ho2  1  0.750  0.915  0.137  1.0
  Ho  Ho3  1  0.750  0.415  0.363  1.0
  Mo  Mo4  1  0.250  0.402  0.109  1.0
  Mo  Mo5  1  0.250  0.902  0.391  1.0
  Mo  Mo6  1  0.750  0.598  0.891  1.0
  Mo  Mo7  1  0.750  0.098  0.609  1.0
  C  C8  1  0.250  0.159  0.247  1.0
  C  C9  1  0.250  0.659  0.253  1.0
  C  C10  1  0.750  0.841  0.753  1.0
  C  C11  1  0.750  0.341  0.747  1.0
  C  C12  1  0.250  0.726  0.985  1.0
  C  C13  1  0.250  0.226  0.515  1.0
  C  C14  1  0.750  0.274  0.015  1.0
  C  C15  1  0.750  0.774  0.485  1.0
[/CIF]
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The compound described by HoMoC2 crystallizes in the orthorhombic Pnma space group. Ho(1) is bonded to three equivalent C(2) and four equivalent C(1) atoms to form distorted HoC7 pentagonal bipyramids that share corners with four equivalent Ho(1)C7 pentagonal bipyramids, corners with three equivalent Mo(1)C5 trigonal bipyramids, edges with four equivalent Ho(1)C7 pentagonal bipyramids, edges with seven equivalent Mo(1)C5 trigonal bipyramids, and faces with two equivalent Ho(1)C7 pentagonal bipyramids. Mo(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form MoC5 trigonal bipyramids that share corners with three equivalent Ho(1)C7 pentagonal bipyramids, corners with four equivalent Mo(1)C5 trigonal bipyramids, edges with seven equivalent Ho(1)C7 pentagonal bipyramids, and edges with two equivalent Mo(1)C5 trigonal bipyramids. There are two inequivalent C sites. In the first C site, C(1) is bonded to four equivalent Ho(1) and two equivalent Mo(1) atoms to form CHo4Mo2 octahedra that share corners with four equivalent C(1)Ho4Mo2 octahedra, corners with nine equivalent C(2)Ho3Mo3 octahedra, edges with two equivalent C(1)Ho4Mo2 octahedra, edges with three equivalent C(2)Ho3Mo3 octahedra,  a faceface with one C(2)Ho3Mo3 octahedra, and faces with two equivalent C(1)Ho4Mo2 octahedra. The corner-sharing octahedral tilt angles range from 11-60°. In the second C site, C(2) is bonded to three equivalent Ho(1) and three equivalent Mo(1) atoms to form CHo3Mo3 octahedra that share corners with nine equivalent C(1)Ho4Mo2 octahedra, edges with three equivalent C(1)Ho4Mo2 octahedra, edges with six equivalent C(2)Ho3Mo3 octahedra, and  a faceface with one C(1)Ho4Mo2 octahedra. The corner-sharing octahedral tilt angles range from 11-60°. is represented by the CIF file [CIF]
data_HoMoC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.379
_cell_length_b   5.691
_cell_length_c   10.775
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   207.204
_cell_formula_units_Z   4
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
  Ho  Ho0  1  0.250  0.085  0.863  1.0
  Ho  Ho1  1  0.250  0.585  0.637  1.0
  Ho  Ho2  1  0.750  0.915  0.137  1.0
  Ho  Ho3  1  0.750  0.415  0.363  1.0
  Mo  Mo4  1  0.250  0.402  0.109  1.0
  Mo  Mo5  1  0.250  0.902  0.391  1.0
  Mo  Mo6  1  0.750  0.598  0.891  1.0
  Mo  Mo7  1  0.750  0.098  0.609  1.0
  C  C8  1  0.250  0.159  0.247  1.0
  C  C9  1  0.250  0.659  0.253  1.0
  C  C10  1  0.750  0.841  0.753  1.0
  C  C11  1  0.750  0.341  0.747  1.0
  C  C12  1  0.250  0.726  0.985  1.0
  C  C13  1  0.250  0.226  0.515  1.0
  C  C14  1  0.750  0.274  0.015  1.0
  C  C15  1  0.750  0.774  0.485  1.0
[/CIF]
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