The compound described by Hf2Ni2Sn crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 10-coordinate geometry to six equivalent Ni(1) and four equivalent Sn(1) atoms. In the second Hf site, Hf(2) is bonded in a 6-coordinate geometry to six equivalent Ni(1) and four equivalent Sn(1) atoms. Ni(1) is bonded in a 6-coordinate geometry to three equivalent Hf(1), three equivalent Hf(2), and two equivalent Sn(1) atoms. Sn(1) is bonded to four equivalent Hf(1), four equivalent Hf(2), and four equivalent Ni(1) atoms to form a mixture of distorted face and corner-sharing SnHf8Ni4 cuboctahedra. is represented by the CIF file [CIF]
data_Hf2Ni2Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.069
_cell_length_b   7.069
_cell_length_c   6.787
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   339.133
_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
  Hf  Hf0  1  0.181  0.181  0.000  1.0
  Hf  Hf1  1  0.681  0.319  0.500  1.0
  Hf  Hf2  1  0.319  0.681  0.500  1.0
  Hf  Hf3  1  0.819  0.819  0.000  1.0
  Hf  Hf4  1  0.652  0.348  0.000  1.0
  Hf  Hf5  1  0.848  0.848  0.500  1.0
  Hf  Hf6  1  0.152  0.152  0.500  1.0
  Hf  Hf7  1  0.348  0.652  0.000  1.0
  Ni  Ni8  1  0.374  0.374  0.284  1.0
  Ni  Ni9  1  0.874  0.126  0.784  1.0
  Ni  Ni10  1  0.126  0.874  0.784  1.0
  Ni  Ni11  1  0.626  0.626  0.284  1.0
  Ni  Ni12  1  0.126  0.874  0.216  1.0
  Ni  Ni13  1  0.874  0.126  0.216  1.0
  Ni  Ni14  1  0.374  0.374  0.716  1.0
  Ni  Ni15  1  0.626  0.626  0.716  1.0
  Sn  Sn16  1  0.500  0.000  0.250  1.0
  Sn  Sn17  1  0.500  0.000  0.750  1.0
  Sn  Sn18  1  0.000  0.500  0.250  1.0
  Sn  Sn19  1  0.000  0.500  0.750  1.0
[/CIF]
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The compound described by Hf2Ni2Sn crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 10-coordinate geometry to six equivalent Ni(1) and four equivalent Sn(1) atoms. In the second Hf site, Hf(2) is bonded in a 6-coordinate geometry to six equivalent Ni(1) and four equivalent Sn(1) atoms. Ni(1) is bonded in a 6-coordinate geometry to three equivalent Hf(1), three equivalent Hf(2), and two equivalent Sn(1) atoms. Sn(1) is bonded to four equivalent Hf(1), four equivalent Hf(2), and four equivalent Ni(1) atoms to form a mixture of distorted face and corner-sharing SnHf8Ni4 cuboctahedra. is represented by the CIF file [CIF]
data_Hf2Ni2Sn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.069
_cell_length_b   7.069
_cell_length_c   6.787
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   339.133
_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
  Hf  Hf0  1  0.181  0.181  0.000  1.0
  Hf  Hf1  1  0.681  0.319  0.500  1.0
  Hf  Hf2  1  0.319  0.681  0.500  1.0
  Hf  Hf3  1  0.819  0.819  0.000  1.0
  Hf  Hf4  1  0.652  0.348  0.000  1.0
  Hf  Hf5  1  0.848  0.848  0.500  1.0
  Hf  Hf6  1  0.152  0.152  0.500  1.0
  Hf  Hf7  1  0.348  0.652  0.000  1.0
  Ni  Ni8  1  0.374  0.374  0.284  1.0
  Ni  Ni9  1  0.874  0.126  0.784  1.0
  Ni  Ni10  1  0.126  0.874  0.784  1.0
  Ni  Ni11  1  0.626  0.626  0.284  1.0
  Ni  Ni12  1  0.126  0.874  0.216  1.0
  Ni  Ni13  1  0.874  0.126  0.216  1.0
  Ni  Ni14  1  0.374  0.374  0.716  1.0
  Ni  Ni15  1  0.626  0.626  0.716  1.0
  Sn  Sn16  1  0.500  0.000  0.250  1.0
  Sn  Sn17  1  0.500  0.000  0.750  1.0
  Sn  Sn18  1  0.000  0.500  0.250  1.0
  Sn  Sn19  1  0.000  0.500  0.750  1.0
[/CIF]
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