The material structure described by ErNiAs is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to six equivalent Ni(1) and six equivalent As(1) atoms to form a mixture of edge and face-sharing ErNi6As6 cuboctahedra. In the second Er site, Er(2) is bonded to six equivalent Ni(1) and six equivalent As(1) atoms to form a mixture of edge and face-sharing ErNi6As6 cuboctahedra. Ni(1) is bonded in a 9-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and three equivalent As(1) atoms. As(1) is bonded in a 9-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_ErNiAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.011
_cell_length_b   4.011
_cell_length_c   15.116
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   210.561
_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
  Er  Er0  1  0.000  0.000  0.250  1.0
  Er  Er1  1  0.000  0.000  0.750  1.0
  Er  Er2  1  0.000  0.000  0.000  1.0
  Er  Er3  1  0.000  0.000  0.500  1.0
  Ni  Ni4  1  0.333  0.667  0.136  1.0
  Ni  Ni5  1  0.667  0.333  0.864  1.0
  Ni  Ni6  1  0.667  0.333  0.636  1.0
  Ni  Ni7  1  0.333  0.667  0.364  1.0
  As  As8  1  0.333  0.667  0.620  1.0
  As  As9  1  0.667  0.333  0.380  1.0
  As  As10  1  0.667  0.333  0.120  1.0
  As  As11  1  0.333  0.667  0.880  1.0
[/CIF]
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The material structure described by ErNiAs is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Er sites. In the first Er site, Er(1) is bonded to six equivalent Ni(1) and six equivalent As(1) atoms to form a mixture of edge and face-sharing ErNi6As6 cuboctahedra. In the second Er site, Er(2) is bonded to six equivalent Ni(1) and six equivalent As(1) atoms to form a mixture of edge and face-sharing ErNi6As6 cuboctahedra. Ni(1) is bonded in a 9-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and three equivalent As(1) atoms. As(1) is bonded in a 9-coordinate geometry to three equivalent Er(1), three equivalent Er(2), and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_ErNiAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.011
_cell_length_b   4.011
_cell_length_c   15.116
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   210.561
_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
  Er  Er0  1  0.000  0.000  0.250  1.0
  Er  Er1  1  0.000  0.000  0.750  1.0
  Er  Er2  1  0.000  0.000  0.000  1.0
  Er  Er3  1  0.000  0.000  0.500  1.0
  Ni  Ni4  1  0.333  0.667  0.136  1.0
  Ni  Ni5  1  0.667  0.333  0.864  1.0
  Ni  Ni6  1  0.667  0.333  0.636  1.0
  Ni  Ni7  1  0.333  0.667  0.364  1.0
  As  As8  1  0.333  0.667  0.620  1.0
  As  As9  1  0.667  0.333  0.380  1.0
  As  As10  1  0.667  0.333  0.120  1.0
  As  As11  1  0.333  0.667  0.880  1.0
[/CIF]
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