data_KNiSn
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.78
_cell_length_b   4.78
_cell_length_c   4.78
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KNiSn
_chemical_formula_sum   'K1 Ni1 Sn1'
_cell_volume   77.3
_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
  K  K0  1  0.0  0.0  0.0  1.0
  Ni  Ni1  1  0.69  0.69  0.69  1.0
  Sn  Sn2  1  0.38  0.38  0.38  1.0

data_KNiSn
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.78
_cell_length_b   4.78
_cell_length_c   11.71
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   KNiSn
_chemical_formula_sum   'K3 Ni3 Sn3'
_cell_volume   231.91
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  K  K0  3  0.0  0.0  0.0  1.0
  Ni  Ni1  3  0.0  0.0  0.31  1.0
  Sn  Sn2  3  0.0  0.0  0.62  1.0

K Ni Sn
K Ni Sn 0 1 - - o 0 1 - o - 0 1 o - - 0 2 - o o 0 2 o - o 0 2 o o - 1 2 o o + 1 2 o + o 1 2 + o o 
KNiSn is half-Heusler structured and crystallizes in the trigonal R3m space group. K(1) is bonded to four equivalent Ni(1) and three equivalent Sn(1) atoms to form distorted KNi4Sn3 hexagonal pyramids that share corners with three equivalent Ni(1)K4Sn3 hexagonal pyramids, corners with six equivalent K(1)Ni4Sn3 hexagonal pyramids, edges with three equivalent Ni(1)K4Sn3 hexagonal pyramids, and edges with six equivalent K(1)Ni4Sn3 hexagonal pyramids. There are three shorter (2.77 Å) and one longer (3.62 Å) K(1)-Ni(1) bond length. All K(1)-Sn(1) bond lengths are 2.82 Å. Ni(1) is bonded to four equivalent K(1) and three equivalent Sn(1) atoms to form distorted NiK4Sn3 hexagonal pyramids that share corners with three equivalent K(1)Ni4Sn3 hexagonal pyramids, corners with six equivalent Ni(1)K4Sn3 hexagonal pyramids, edges with three equivalent K(1)Ni4Sn3 hexagonal pyramids, and edges with six equivalent Ni(1)K4Sn3 hexagonal pyramids. All Ni(1)-Sn(1) bond lengths are 2.77 Å. Sn(1) is bonded in a distorted hexagonal planar geometry to three equivalent K(1) and three equivalent Ni(1) atoms.