The material described by Tm2NiAs2 crystallizes in the hexagonal P6_3/mmc space group. Tm(1) is bonded in a 9-coordinate geometry to three equivalent Ni(1), three equivalent As(1), and three equivalent As(2) atoms. Ni(1) is bonded in a 9-coordinate geometry to six equivalent Tm(1) and three equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Tm(1) atoms to form edge-sharing AsTm6 octahedra. In the second As site, As(2) is bonded in a 9-coordinate geometry to six equivalent Tm(1) and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Tm2NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.043
_cell_length_b   4.043
_cell_length_c   13.925
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   197.116
_cell_formula_units_Z   2
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
  Tm  Tm0  1  0.333  0.667  0.882  1.0
  Tm  Tm1  1  0.667  0.333  0.382  1.0
  Tm  Tm2  1  0.667  0.333  0.118  1.0
  Tm  Tm3  1  0.333  0.667  0.618  1.0
  Ni  Ni4  1  0.000  0.000  0.750  1.0
  Ni  Ni5  1  0.000  0.000  0.250  1.0
  As  As6  1  0.000  0.000  0.000  1.0
  As  As7  1  0.333  0.667  0.250  1.0
  As  As8  1  0.667  0.333  0.750  1.0
  As  As9  1  0.000  0.000  0.500  1.0
[/CIF]
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The material described by Tm2NiAs2 crystallizes in the hexagonal P6_3/mmc space group. Tm(1) is bonded in a 9-coordinate geometry to three equivalent Ni(1), three equivalent As(1), and three equivalent As(2) atoms. Ni(1) is bonded in a 9-coordinate geometry to six equivalent Tm(1) and three equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(1) is bonded to six equivalent Tm(1) atoms to form edge-sharing AsTm6 octahedra. In the second As site, As(2) is bonded in a 9-coordinate geometry to six equivalent Tm(1) and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Tm2NiAs2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.043
_cell_length_b   4.043
_cell_length_c   13.925
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   197.116
_cell_formula_units_Z   2
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
  Tm  Tm0  1  0.333  0.667  0.882  1.0
  Tm  Tm1  1  0.667  0.333  0.382  1.0
  Tm  Tm2  1  0.667  0.333  0.118  1.0
  Tm  Tm3  1  0.333  0.667  0.618  1.0
  Ni  Ni4  1  0.000  0.000  0.750  1.0
  Ni  Ni5  1  0.000  0.000  0.250  1.0
  As  As6  1  0.000  0.000  0.000  1.0
  As  As7  1  0.333  0.667  0.250  1.0
  As  As8  1  0.667  0.333  0.750  1.0
  As  As9  1  0.000  0.000  0.500  1.0
[/CIF]
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