The structure described by Na5Ni9As7 crystallizes in the hexagonal P-6 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 12-coordinate geometry to one Ni(3), two equivalent Ni(2), four equivalent Ni(1), one As(1), two equivalent As(2), and two equivalent As(3) atoms. In the second Na site, Na(2) is bonded in a 18-coordinate geometry to three equivalent Ni(1), three equivalent Ni(2), six equivalent Ni(3), and six equivalent As(1) atoms. In the third Na site, Na(3) is bonded in a 15-coordinate geometry to three equivalent Ni(3), six equivalent Ni(2), and six equivalent As(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to one Na(2), four equivalent Na(1), one Ni(2), two equivalent Ni(3), one As(2), one As(3), and two equivalent As(1) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), two equivalent Na(3), one Ni(1), two equivalent As(1), and two equivalent As(2) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), two equivalent Na(2), two equivalent Ni(1), two equivalent As(1), and two equivalent As(2) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second As site, As(2) is bonded in a 9-coordinate geometry to two equivalent Na(1), two equivalent Na(3), one Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the third As site, As(3) is bonded in a 9-coordinate geometry to six equivalent Na(1) and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Na5Ni9As7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.681
_cell_length_b   9.681
_cell_length_c   3.981
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   323.165
_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
  Na  Na0  1  0.222  0.116  0.500  1.0
  Na  Na1  1  0.884  0.106  0.500  1.0
  Na  Na2  1  0.894  0.778  0.500  1.0
  Na  Na3  1  0.333  0.667  0.000  1.0
  Na  Na4  1  0.667  0.333  0.500  1.0
  Ni  Ni5  1  0.128  0.299  0.000  1.0
  Ni  Ni6  1  0.701  0.829  0.000  1.0
  Ni  Ni7  1  0.171  0.872  0.000  1.0
  Ni  Ni8  1  0.424  0.382  0.000  1.0
  Ni  Ni9  1  0.618  0.042  0.000  1.0
  Ni  Ni10  1  0.958  0.576  0.000  1.0
  Ni  Ni11  1  0.052  0.439  0.500  1.0
  Ni  Ni12  1  0.561  0.613  0.500  1.0
  Ni  Ni13  1  0.387  0.948  0.500  1.0
  As  As14  1  0.290  0.420  0.500  1.0
  As  As15  1  0.580  0.870  0.500  1.0
  As  As16  1  0.130  0.710  0.500  1.0
  As  As17  1  0.421  0.113  0.000  1.0
  As  As18  1  0.887  0.308  0.000  1.0
  As  As19  1  0.692  0.579  0.000  1.0
  As  As20  1  0.000  0.000  0.000  1.0
[/CIF]
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The structure described by Na5Ni9As7 crystallizes in the hexagonal P-6 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 12-coordinate geometry to one Ni(3), two equivalent Ni(2), four equivalent Ni(1), one As(1), two equivalent As(2), and two equivalent As(3) atoms. In the second Na site, Na(2) is bonded in a 18-coordinate geometry to three equivalent Ni(1), three equivalent Ni(2), six equivalent Ni(3), and six equivalent As(1) atoms. In the third Na site, Na(3) is bonded in a 15-coordinate geometry to three equivalent Ni(3), six equivalent Ni(2), and six equivalent As(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 12-coordinate geometry to one Na(2), four equivalent Na(1), one Ni(2), two equivalent Ni(3), one As(2), one As(3), and two equivalent As(1) atoms. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), two equivalent Na(3), one Ni(1), two equivalent As(1), and two equivalent As(2) atoms. In the third Ni site, Ni(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), two equivalent Na(2), two equivalent Ni(1), two equivalent As(1), and two equivalent As(2) atoms. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 9-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the second As site, As(2) is bonded in a 9-coordinate geometry to two equivalent Na(1), two equivalent Na(3), one Ni(1), two equivalent Ni(2), and two equivalent Ni(3) atoms. In the third As site, As(3) is bonded in a 9-coordinate geometry to six equivalent Na(1) and three equivalent Ni(1) atoms. is represented by the CIF card [CIF]
data_Na5Ni9As7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.681
_cell_length_b   9.681
_cell_length_c   3.981
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   323.165
_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
  Na  Na0  1  0.222  0.116  0.500  1.0
  Na  Na1  1  0.884  0.106  0.500  1.0
  Na  Na2  1  0.894  0.778  0.500  1.0
  Na  Na3  1  0.333  0.667  0.000  1.0
  Na  Na4  1  0.667  0.333  0.500  1.0
  Ni  Ni5  1  0.128  0.299  0.000  1.0
  Ni  Ni6  1  0.701  0.829  0.000  1.0
  Ni  Ni7  1  0.171  0.872  0.000  1.0
  Ni  Ni8  1  0.424  0.382  0.000  1.0
  Ni  Ni9  1  0.618  0.042  0.000  1.0
  Ni  Ni10  1  0.958  0.576  0.000  1.0
  Ni  Ni11  1  0.052  0.439  0.500  1.0
  Ni  Ni12  1  0.561  0.613  0.500  1.0
  Ni  Ni13  1  0.387  0.948  0.500  1.0
  As  As14  1  0.290  0.420  0.500  1.0
  As  As15  1  0.580  0.870  0.500  1.0
  As  As16  1  0.130  0.710  0.500  1.0
  As  As17  1  0.421  0.113  0.000  1.0
  As  As18  1  0.887  0.308  0.000  1.0
  As  As19  1  0.692  0.579  0.000  1.0
  As  As20  1  0.000  0.000  0.000  1.0
[/CIF]
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