The crystal structure described by UMnC2 crystallizes in the orthorhombic Pnma space group. U(1) is bonded to three equivalent C(2) and four equivalent C(1) atoms to form distorted UC7 pentagonal bipyramids that share corners with four equivalent U(1)C7 pentagonal bipyramids, corners with three equivalent Mn(1)C5 trigonal bipyramids, edges with four equivalent U(1)C7 pentagonal bipyramids, edges with seven equivalent Mn(1)C5 trigonal bipyramids, and faces with two equivalent U(1)C7 pentagonal bipyramids. Mn(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form MnC5 trigonal bipyramids that share corners with three equivalent U(1)C7 pentagonal bipyramids, corners with four equivalent Mn(1)C5 trigonal bipyramids, edges with seven equivalent U(1)C7 pentagonal bipyramids, and edges with two equivalent Mn(1)C5 trigonal bipyramids. There are two inequivalent C sites. In the first C site, C(1) is bonded to four equivalent U(1) and two equivalent Mn(1) atoms to form CU4Mn2 octahedra that share corners with four equivalent C(1)U4Mn2 octahedra, corners with nine equivalent C(2)U3Mn3 octahedra, edges with two equivalent C(1)U4Mn2 octahedra, edges with three equivalent C(2)U3Mn3 octahedra,  a faceface with one C(2)U3Mn3 octahedra, and faces with two equivalent C(1)U4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 13-60°. In the second C site, C(2) is bonded to three equivalent U(1) and three equivalent Mn(1) atoms to form CU3Mn3 octahedra that share corners with nine equivalent C(1)U4Mn2 octahedra, edges with three equivalent C(1)U4Mn2 octahedra, edges with six equivalent C(2)U3Mn3 octahedra, and  a faceface with one C(1)U4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 13-60°. is represented by the CIF card [CIF]
data_UMnC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.210
_cell_length_b   5.500
_cell_length_c   10.721
_cell_angle_alpha   90.002
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.244
_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
  U  U0  1  0.250  0.584  0.857  1.0
  U  U1  1  0.750  0.416  0.143  1.0
  U  U2  1  0.750  0.916  0.357  1.0
  U  U3  1  0.250  0.084  0.643  1.0
  Mn  Mn4  1  0.250  0.917  0.102  1.0
  Mn  Mn5  1  0.750  0.083  0.898  1.0
  Mn  Mn6  1  0.750  0.583  0.602  1.0
  Mn  Mn7  1  0.250  0.417  0.398  1.0
  C  C8  1  0.250  0.661  0.248  1.0
  C  C9  1  0.750  0.339  0.752  1.0
  C  C10  1  0.750  0.839  0.748  1.0
  C  C11  1  0.250  0.161  0.252  1.0
  C  C12  1  0.250  0.726  0.511  1.0
  C  C13  1  0.750  0.274  0.489  1.0
  C  C14  1  0.750  0.774  0.011  1.0
  C  C15  1  0.250  0.226  0.989  1.0
[/CIF]
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The crystal structure described by UMnC2 crystallizes in the orthorhombic Pnma space group. U(1) is bonded to three equivalent C(2) and four equivalent C(1) atoms to form distorted UC7 pentagonal bipyramids that share corners with four equivalent U(1)C7 pentagonal bipyramids, corners with three equivalent Mn(1)C5 trigonal bipyramids, edges with four equivalent U(1)C7 pentagonal bipyramids, edges with seven equivalent Mn(1)C5 trigonal bipyramids, and faces with two equivalent U(1)C7 pentagonal bipyramids. Mn(1) is bonded to two equivalent C(1) and three equivalent C(2) atoms to form MnC5 trigonal bipyramids that share corners with three equivalent U(1)C7 pentagonal bipyramids, corners with four equivalent Mn(1)C5 trigonal bipyramids, edges with seven equivalent U(1)C7 pentagonal bipyramids, and edges with two equivalent Mn(1)C5 trigonal bipyramids. There are two inequivalent C sites. In the first C site, C(1) is bonded to four equivalent U(1) and two equivalent Mn(1) atoms to form CU4Mn2 octahedra that share corners with four equivalent C(1)U4Mn2 octahedra, corners with nine equivalent C(2)U3Mn3 octahedra, edges with two equivalent C(1)U4Mn2 octahedra, edges with three equivalent C(2)U3Mn3 octahedra,  a faceface with one C(2)U3Mn3 octahedra, and faces with two equivalent C(1)U4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 13-60°. In the second C site, C(2) is bonded to three equivalent U(1) and three equivalent Mn(1) atoms to form CU3Mn3 octahedra that share corners with nine equivalent C(1)U4Mn2 octahedra, edges with three equivalent C(1)U4Mn2 octahedra, edges with six equivalent C(2)U3Mn3 octahedra, and  a faceface with one C(1)U4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 13-60°. is represented by the CIF card [CIF]
data_UMnC2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.210
_cell_length_b   5.500
_cell_length_c   10.721
_cell_angle_alpha   90.002
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.244
_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
  U  U0  1  0.250  0.584  0.857  1.0
  U  U1  1  0.750  0.416  0.143  1.0
  U  U2  1  0.750  0.916  0.357  1.0
  U  U3  1  0.250  0.084  0.643  1.0
  Mn  Mn4  1  0.250  0.917  0.102  1.0
  Mn  Mn5  1  0.750  0.083  0.898  1.0
  Mn  Mn6  1  0.750  0.583  0.602  1.0
  Mn  Mn7  1  0.250  0.417  0.398  1.0
  C  C8  1  0.250  0.661  0.248  1.0
  C  C9  1  0.750  0.339  0.752  1.0
  C  C10  1  0.750  0.839  0.748  1.0
  C  C11  1  0.250  0.161  0.252  1.0
  C  C12  1  0.250  0.726  0.511  1.0
  C  C13  1  0.750  0.274  0.489  1.0
  C  C14  1  0.750  0.774  0.011  1.0
  C  C15  1  0.250  0.226  0.989  1.0
[/CIF]
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