The material structure described by Ni6SnSe2 crystallizes in the tetragonal I4mm space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(2), four equivalent Ni(3), and four equivalent Sn(1) atoms to form NiNi8Sn4 cuboctahedra that share corners with four equivalent Ni(1)Ni8Sn4 cuboctahedra, faces with four equivalent Ni(1)Ni8Sn4 cuboctahedra, and faces with four equivalent Sn(1)Ni12 cuboctahedra. In the second Ni site, Ni(2) is bonded in a distorted water-like geometry to two equivalent Ni(1), two equivalent Sn(1), and two equivalent Se(1) atoms. In the third Ni site, Ni(3) is bonded in a distorted water-like geometry to two equivalent Ni(1), two equivalent Sn(1), and two equivalent Se(2) atoms. In the fourth Ni site, Ni(4) is bonded in a 5-coordinate geometry to one Se(2) and four equivalent Se(1) atoms. Sn(1) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Ni(3) atoms to form SnNi12 cuboctahedra that share corners with four equivalent Sn(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Ni8Sn4 cuboctahedra, and faces with four equivalent Sn(1)Ni12 cuboctahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(4) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Ni(4) and four equivalent Ni(3) atoms. is represented by the CIF file [CIF]
data_Ni6SnSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.760
_cell_length_b   9.760
_cell_length_c   9.760
_cell_angle_alpha   158.199
_cell_angle_beta   158.199
_cell_angle_gamma   31.023
_symmetry_Int_Tables_number   1
_cell_volume   128.125
_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
  Ni  Ni0  1  0.501  0.501  0.000  1.0
  Ni  Ni1  1  0.900  0.400  0.500  1.0
  Ni  Ni2  1  0.400  0.900  0.500  1.0
  Ni  Ni3  1  0.102  0.602  0.500  1.0
  Ni  Ni4  1  0.602  0.102  0.500  1.0
  Ni  Ni5  1  0.801  0.801  0.000  1.0
  Sn  Sn6  1  0.000  0.000  0.000  1.0
  Se  Se7  1  0.316  0.316  0.000  1.0
  Se  Se8  1  0.678  0.678  0.000  1.0
[/CIF]
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The material structure described by Ni6SnSe2 crystallizes in the tetragonal I4mm space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(2), four equivalent Ni(3), and four equivalent Sn(1) atoms to form NiNi8Sn4 cuboctahedra that share corners with four equivalent Ni(1)Ni8Sn4 cuboctahedra, faces with four equivalent Ni(1)Ni8Sn4 cuboctahedra, and faces with four equivalent Sn(1)Ni12 cuboctahedra. In the second Ni site, Ni(2) is bonded in a distorted water-like geometry to two equivalent Ni(1), two equivalent Sn(1), and two equivalent Se(1) atoms. In the third Ni site, Ni(3) is bonded in a distorted water-like geometry to two equivalent Ni(1), two equivalent Sn(1), and two equivalent Se(2) atoms. In the fourth Ni site, Ni(4) is bonded in a 5-coordinate geometry to one Se(2) and four equivalent Se(1) atoms. Sn(1) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Ni(3) atoms to form SnNi12 cuboctahedra that share corners with four equivalent Sn(1)Ni12 cuboctahedra, faces with four equivalent Ni(1)Ni8Sn4 cuboctahedra, and faces with four equivalent Sn(1)Ni12 cuboctahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 8-coordinate geometry to four equivalent Ni(2) and four equivalent Ni(4) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Ni(4) and four equivalent Ni(3) atoms. is represented by the CIF file [CIF]
data_Ni6SnSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.760
_cell_length_b   9.760
_cell_length_c   9.760
_cell_angle_alpha   158.199
_cell_angle_beta   158.199
_cell_angle_gamma   31.023
_symmetry_Int_Tables_number   1
_cell_volume   128.125
_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
  Ni  Ni0  1  0.501  0.501  0.000  1.0
  Ni  Ni1  1  0.900  0.400  0.500  1.0
  Ni  Ni2  1  0.400  0.900  0.500  1.0
  Ni  Ni3  1  0.102  0.602  0.500  1.0
  Ni  Ni4  1  0.602  0.102  0.500  1.0
  Ni  Ni5  1  0.801  0.801  0.000  1.0
  Sn  Sn6  1  0.000  0.000  0.000  1.0
  Se  Se7  1  0.316  0.316  0.000  1.0
  Se  Se8  1  0.678  0.678  0.000  1.0
[/CIF]
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