data_Nd2C3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.46
_cell_length_b   7.46
_cell_length_c   7.46
_cell_angle_alpha   109.47
_cell_angle_beta   109.47
_cell_angle_gamma   109.47
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Nd2C3
_chemical_formula_sum   'Nd8 C12'
_cell_volume   319.9
_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
  Nd  Nd0  1  0.45  0.75  0.55  1.0
  Nd  Nd1  1  0.71  0.29  0.6  1.0
  Nd  Nd2  1  0.71  0.71  0.71  1.0
  Nd  Nd3  1  0.6  0.71  0.29  1.0
  Nd  Nd4  1  0.86  0.86  0.86  1.0
  Nd  Nd5  1  0.75  0.55  0.45  1.0
  Nd  Nd6  1  0.55  0.45  0.75  1.0
  Nd  Nd7  1  0.29  0.6  0.71  1.0
  C  C8  1  0.85  0.57  0.31  1.0
  C  C9  1  0.85  0.9  0.31  1.0
  C  C10  1  0.41  0.31  0.15  1.0
  C  C11  1  0.31  0.85  0.9  1.0
  C  C12  1  0.9  0.31  0.85  1.0
  C  C13  1  0.31  0.15  0.41  1.0
  C  C14  1  0.15  0.74  0.31  1.0
  C  C15  1  0.31  0.85  0.57  1.0
  C  C16  1  0.15  0.41  0.31  1.0
  C  C17  1  0.74  0.31  0.15  1.0
  C  C18  1  0.57  0.31  0.85  1.0
  C  C19  1  0.31  0.15  0.74  1.0

data_Nd2C3
_symmetry_space_group_name_H-M   R3
_cell_length_a   12.19
_cell_length_b   12.19
_cell_length_c   7.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   Nd2C3
_chemical_formula_sum   'Nd24 C36'
_cell_volume   959.69
_cell_formula_units_Z   12
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  'x+2/3, y+1/3, z+1/3'
  5  '-y+2/3, x-y+1/3, z+1/3'
  6  '-x+y+2/3, -x+1/3, z+1/3'
  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'
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
  Nd  Nd0  9  0.07  0.24  0.53  1.0
  Nd  Nd1  9  0.17  0.14  0.58  1.0
  Nd  Nd2  3  0.0  0.0  0.71  1.0
  Nd  Nd3  3  0.0  0.0  0.86  1.0
  C  C4  9  0.01  0.58  0.73  1.0
  C  C5  9  0.02  0.88  0.29  1.0
  C  C6  9  0.07  0.67  0.24  1.0
  C  C7  9  0.16  0.38  0.68  1.0

Nd Nd Nd Nd Nd Nd Nd Nd C C C C C C C C C C C C
Nd2C3 crystallizes in the trigonal R3 space group. There are four inequivalent Nd sites. In the first Nd site, Nd(1) is bonded in a distorted single-bond geometry to one Nd(3), one C(1), and one C(3) atom. The Nd(1)-Nd(3) bond length is 2.12 Å. The Nd(1)-C(1) bond length is 1.42 Å. The Nd(1)-C(3) bond length is 2.26 Å. In the second Nd site, Nd(2) is bonded in a 1-coordinate geometry to one C(2) and one C(3) atom. The Nd(2)-C(2) bond length is 1.83 Å. The Nd(2)-C(3) bond length is 2.48 Å. In the third Nd site, Nd(3) is bonded in a distorted tetrahedral geometry to one Nd(4) and three equivalent Nd(1) atoms. The Nd(3)-Nd(4) bond length is 1.15 Å. In the fourth Nd site, Nd(4) is bonded in a distorted tetrahedral geometry to one Nd(3) and three equivalent C(2) atoms. All Nd(4)-C(2) bond lengths are 3.30 Å. There are four inequivalent C sites. In the first C site, C(1) is bonded in a single-bond geometry to one Nd(1) and one C(4) atom. The C(1)-C(4) bond length is 1.60 Å. In the second C site, C(2) is bonded in a single-bond geometry to one Nd(2) and one Nd(4) atom. In the third C site, C(3) is bonded in a 2-coordinate geometry to one Nd(1) and one Nd(2) atom. In the fourth C site, C(4) is bonded in a 1-coordinate geometry to one C(1) atom.