The structure described by Ba2NiSi3 crystallizes in the hexagonal P-62m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Ni(1), two equivalent Si(1), and eight equivalent Si(2) atoms to form a mixture of distorted corner and face-sharing BaSi10Ni2 cuboctahedra. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one Ni(2), four equivalent Si(1), and four equivalent Si(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent Ba(1) and six equivalent Si(2) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ba(2) and six equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted q6 geometry to two equivalent Ba(1), four equivalent Ba(2), two equivalent Ni(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), two equivalent Ni(1), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Si3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.480
_cell_length_b   11.480
_cell_length_c   3.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   443.850
_cell_formula_units_Z   3
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
  Ba  Ba0  1  0.618  0.000  1.000  1.0
  Ba  Ba1  1  0.382  0.382  1.000  1.0
  Ba  Ba2  1  0.000  0.618  1.000  1.0
  Ba  Ba3  1  0.000  0.287  0.000  1.0
  Ba  Ba4  1  0.713  0.713  0.000  1.0
  Ba  Ba5  1  0.287  1.000  1.000  1.0
  Si  Si6  1  0.878  0.000  0.500  1.0
  Si  Si7  1  0.000  0.878  0.500  1.0
  Si  Si8  1  0.122  0.122  0.500  1.0
  Si  Si9  1  0.778  0.316  0.500  1.0
  Si  Si10  1  0.684  0.462  0.500  1.0
  Si  Si11  1  0.316  0.778  0.500  1.0
  Si  Si12  1  0.222  0.538  0.500  1.0
  Si  Si13  1  0.462  0.684  0.500  1.0
  Si  Si14  1  0.538  0.222  0.500  1.0
  Ni  Ni15  1  0.333  0.667  0.000  1.0
  Ni  Ni16  1  0.667  0.333  1.000  1.0
  Ni  Ni17  1  0.000  0.000  1.000  1.0
[/CIF]
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The structure described by Ba2NiSi3 crystallizes in the hexagonal P-62m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent Ni(1), two equivalent Si(1), and eight equivalent Si(2) atoms to form a mixture of distorted corner and face-sharing BaSi10Ni2 cuboctahedra. In the second Ba site, Ba(2) is bonded in a 9-coordinate geometry to one Ni(2), four equivalent Si(1), and four equivalent Si(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent Ba(1) and six equivalent Si(2) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to three equivalent Ba(2) and six equivalent Si(1) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted q6 geometry to two equivalent Ba(1), four equivalent Ba(2), two equivalent Ni(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), two equivalent Ni(1), and two equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Si3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.480
_cell_length_b   11.480
_cell_length_c   3.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.999
_symmetry_Int_Tables_number   1
_cell_volume   443.850
_cell_formula_units_Z   3
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
  Ba  Ba0  1  0.618  0.000  1.000  1.0
  Ba  Ba1  1  0.382  0.382  1.000  1.0
  Ba  Ba2  1  0.000  0.618  1.000  1.0
  Ba  Ba3  1  0.000  0.287  0.000  1.0
  Ba  Ba4  1  0.713  0.713  0.000  1.0
  Ba  Ba5  1  0.287  1.000  1.000  1.0
  Si  Si6  1  0.878  0.000  0.500  1.0
  Si  Si7  1  0.000  0.878  0.500  1.0
  Si  Si8  1  0.122  0.122  0.500  1.0
  Si  Si9  1  0.778  0.316  0.500  1.0
  Si  Si10  1  0.684  0.462  0.500  1.0
  Si  Si11  1  0.316  0.778  0.500  1.0
  Si  Si12  1  0.222  0.538  0.500  1.0
  Si  Si13  1  0.462  0.684  0.500  1.0
  Si  Si14  1  0.538  0.222  0.500  1.0
  Ni  Ni15  1  0.333  0.667  0.000  1.0
  Ni  Ni16  1  0.667  0.333  1.000  1.0
  Ni  Ni17  1  0.000  0.000  1.000  1.0
[/CIF]
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