The compound described by Er4Ni2C5 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one C(3), two equivalent C(2), and four equivalent C(1) atoms. In the second Er site, Er(2) is bonded to eight equivalent Ni(1) and four equivalent C(2) atoms to form distorted ErNi8C4 cuboctahedra that share corners with four equivalent C(1)Er5NiC pentagonal bipyramids, edges with four equivalent Er(2)Ni8C4 cuboctahedra, edges with four equivalent C(1)Er5NiC pentagonal bipyramids, and faces with four equivalent Er(2)Ni8C4 cuboctahedra. In the third Er site, Er(3) is bonded to two equivalent C(1) and four equivalent C(3) atoms to form a mixture of corner and edge-sharing ErC6 octahedra. The corner-sharing octahedral tilt angles are 1°. Ni(1) is bonded in a 3-coordinate geometry to four equivalent Er(2), one C(1), and two equivalent C(2) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Er(3), four equivalent Er(1), one Ni(1), and one C(2) atom to form distorted CEr5NiC pentagonal bipyramids that share corners with two equivalent Er(2)Ni8C4 cuboctahedra, corners with five equivalent C(1)Er5NiC pentagonal bipyramids, edges with two equivalent Er(2)Ni8C4 cuboctahedra, edges with four equivalent C(3)Er6 octahedra, and edges with four equivalent C(1)Er5NiC pentagonal bipyramids. In the second C site, C(2) is bonded in a 7-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Ni(1), and one C(1) atom. In the third C site, C(3) is bonded to two equivalent Er(1) and four equivalent Er(3) atoms to form CEr6 octahedra that share corners with four equivalent C(3)Er6 octahedra, edges with four equivalent C(3)Er6 octahedra, and edges with eight equivalent C(1)Er5NiC pentagonal bipyramids. The corner-sharing octahedral tilt angles are 1°. is represented by the CIF file [CIF]
data_Er4Ni2C5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.574
_cell_length_b   3.653
_cell_length_c   11.458
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.618
_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
  Er  Er0  1  0.500  0.503  0.204  1.0
  Er  Er1  1  0.500  0.503  0.796  1.0
  Er  Er2  1  0.500  0.210  0.500  1.0
  Er  Er3  1  0.000  1.000  0.000  1.0
  Ni  Ni4  1  0.000  0.699  0.385  1.0
  Ni  Ni5  1  0.000  0.699  0.615  1.0
  C  C6  1  0.000  0.999  0.229  1.0
  C  C7  1  0.000  0.999  0.771  1.0
  C  C8  1  0.000  0.198  0.333  1.0
  C  C9  1  0.000  0.198  0.667  1.0
  C  C10  1  0.500  0.493  0.000  1.0
[/CIF]
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The compound described by Er4Ni2C5 crystallizes in the orthorhombic Pmm2 space group. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 7-coordinate geometry to one C(3), two equivalent C(2), and four equivalent C(1) atoms. In the second Er site, Er(2) is bonded to eight equivalent Ni(1) and four equivalent C(2) atoms to form distorted ErNi8C4 cuboctahedra that share corners with four equivalent C(1)Er5NiC pentagonal bipyramids, edges with four equivalent Er(2)Ni8C4 cuboctahedra, edges with four equivalent C(1)Er5NiC pentagonal bipyramids, and faces with four equivalent Er(2)Ni8C4 cuboctahedra. In the third Er site, Er(3) is bonded to two equivalent C(1) and four equivalent C(3) atoms to form a mixture of corner and edge-sharing ErC6 octahedra. The corner-sharing octahedral tilt angles are 1°. Ni(1) is bonded in a 3-coordinate geometry to four equivalent Er(2), one C(1), and two equivalent C(2) atoms. There are three inequivalent C sites. In the first C site, C(1) is bonded to one Er(3), four equivalent Er(1), one Ni(1), and one C(2) atom to form distorted CEr5NiC pentagonal bipyramids that share corners with two equivalent Er(2)Ni8C4 cuboctahedra, corners with five equivalent C(1)Er5NiC pentagonal bipyramids, edges with two equivalent Er(2)Ni8C4 cuboctahedra, edges with four equivalent C(3)Er6 octahedra, and edges with four equivalent C(1)Er5NiC pentagonal bipyramids. In the second C site, C(2) is bonded in a 7-coordinate geometry to two equivalent Er(1), two equivalent Er(2), two equivalent Ni(1), and one C(1) atom. In the third C site, C(3) is bonded to two equivalent Er(1) and four equivalent Er(3) atoms to form CEr6 octahedra that share corners with four equivalent C(3)Er6 octahedra, edges with four equivalent C(3)Er6 octahedra, and edges with eight equivalent C(1)Er5NiC pentagonal bipyramids. The corner-sharing octahedral tilt angles are 1°. is represented by the CIF file [CIF]
data_Er4Ni2C5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.574
_cell_length_b   3.653
_cell_length_c   11.458
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   149.618
_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
  Er  Er0  1  0.500  0.503  0.204  1.0
  Er  Er1  1  0.500  0.503  0.796  1.0
  Er  Er2  1  0.500  0.210  0.500  1.0
  Er  Er3  1  0.000  1.000  0.000  1.0
  Ni  Ni4  1  0.000  0.699  0.385  1.0
  Ni  Ni5  1  0.000  0.699  0.615  1.0
  C  C6  1  0.000  0.999  0.229  1.0
  C  C7  1  0.000  0.999  0.771  1.0
  C  C8  1  0.000  0.198  0.333  1.0
  C  C9  1  0.000  0.198  0.667  1.0
  C  C10  1  0.500  0.493  0.000  1.0
[/CIF]
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