The compound described by Ta2Ni3Si is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. Ta(1) is bonded in a 16-coordinate geometry to four equivalent Ta(1), nine equivalent Ni(1), and three equivalent Si(1) atoms. Ni(1) is bonded to six equivalent Ta(1), four equivalent Ni(1), and two equivalent Si(1) atoms to form NiTa6Si2Ni4 cuboctahedra that share corners with four equivalent Si(1)Ta6Ni6 cuboctahedra, corners with fourteen equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, edges with six equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, faces with six equivalent Si(1)Ta6Ni6 cuboctahedra, and faces with twelve equivalent Ni(1)Ta6Si2Ni4 cuboctahedra. Si(1) is bonded to six equivalent Ta(1) and six equivalent Ni(1) atoms to form SiTa6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, edges with six equivalent Si(1)Ta6Ni6 cuboctahedra, faces with two equivalent Si(1)Ta6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Ta6Si2Ni4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta2SiNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.853
_cell_length_b   4.853
_cell_length_c   7.669
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   156.423
_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
  Ta  Ta0  1  0.333  0.667  0.942  1.0
  Ta  Ta1  1  0.667  0.333  0.058  1.0
  Ta  Ta2  1  0.667  0.333  0.442  1.0
  Ta  Ta3  1  0.333  0.667  0.558  1.0
  Si  Si4  1  0.000  0.000  0.000  1.0
  Si  Si5  1  0.000  0.000  0.500  1.0
  Ni  Ni6  1  0.832  0.168  0.750  1.0
  Ni  Ni7  1  0.832  0.663  0.750  1.0
  Ni  Ni8  1  0.337  0.168  0.750  1.0
  Ni  Ni9  1  0.168  0.832  0.250  1.0
  Ni  Ni10  1  0.168  0.337  0.250  1.0
  Ni  Ni11  1  0.663  0.832  0.250  1.0
[/CIF]
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The compound described by Ta2Ni3Si is Hexagonal Laves-derived structured and crystallizes in the hexagonal P6_3/mmc space group. Ta(1) is bonded in a 16-coordinate geometry to four equivalent Ta(1), nine equivalent Ni(1), and three equivalent Si(1) atoms. Ni(1) is bonded to six equivalent Ta(1), four equivalent Ni(1), and two equivalent Si(1) atoms to form NiTa6Si2Ni4 cuboctahedra that share corners with four equivalent Si(1)Ta6Ni6 cuboctahedra, corners with fourteen equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, edges with six equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, faces with six equivalent Si(1)Ta6Ni6 cuboctahedra, and faces with twelve equivalent Ni(1)Ta6Si2Ni4 cuboctahedra. Si(1) is bonded to six equivalent Ta(1) and six equivalent Ni(1) atoms to form SiTa6Ni6 cuboctahedra that share corners with twelve equivalent Ni(1)Ta6Si2Ni4 cuboctahedra, edges with six equivalent Si(1)Ta6Ni6 cuboctahedra, faces with two equivalent Si(1)Ta6Ni6 cuboctahedra, and faces with eighteen equivalent Ni(1)Ta6Si2Ni4 cuboctahedra. is represented by the CIF card [CIF]
data_Ta2SiNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.853
_cell_length_b   4.853
_cell_length_c   7.669
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   156.423
_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
  Ta  Ta0  1  0.333  0.667  0.942  1.0
  Ta  Ta1  1  0.667  0.333  0.058  1.0
  Ta  Ta2  1  0.667  0.333  0.442  1.0
  Ta  Ta3  1  0.333  0.667  0.558  1.0
  Si  Si4  1  0.000  0.000  0.000  1.0
  Si  Si5  1  0.000  0.000  0.500  1.0
  Ni  Ni6  1  0.832  0.168  0.750  1.0
  Ni  Ni7  1  0.832  0.663  0.750  1.0
  Ni  Ni8  1  0.337  0.168  0.750  1.0
  Ni  Ni9  1  0.168  0.832  0.250  1.0
  Ni  Ni10  1  0.168  0.337  0.250  1.0
  Ni  Ni11  1  0.663  0.832  0.250  1.0
[/CIF]
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