The material structure described by KNaSO4 crystallizes in the trigonal P3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(3), three equivalent O(1), and six equivalent O(2) atoms. In the second K site, K(2) is bonded to three equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted KO12 cuboctahedra that share edges with six equivalent K(2)O12 cuboctahedra, edges with three equivalent S(1)O4 tetrahedra, edges with three equivalent S(2)O4 tetrahedra, faces with three equivalent Na(2)O7 hexagonal pyramids, and faces with two equivalent Na(1)O6 octahedra. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NaO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, edges with three equivalent Na(2)O7 hexagonal pyramids, and faces with two equivalent K(2)O12 cuboctahedra. In the second Na site, Na(2) is bonded to one O(4) and six equivalent O(1) atoms to form distorted NaO7 hexagonal pyramids that share corners with six equivalent Na(2)O7 hexagonal pyramids,  a cornercorner with one S(2)O4 tetrahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent S(1)O4 tetrahedra, and faces with three equivalent K(2)O12 cuboctahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3) and three equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, edges with three equivalent K(2)O12 cuboctahedra, and edges with three equivalent Na(2)O7 hexagonal pyramids. The corner-sharing octahedral tilt angles are 17°. In the second S site, S(2) is bonded to one O(4) and three equivalent O(2) atoms to form SO4 tetrahedra that share  a cornercorner with one Na(2)O7 hexagonal pyramid, corners with three equivalent Na(1)O6 octahedra, and edges with three equivalent K(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one K(2), one Na(1), two equivalent Na(2), and one S(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Na(1), and one S(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one K(1), three equivalent K(2), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to three equivalent K(2), one Na(2), and one S(2) atom. is represented by the CIF card [CIF]
data_KNaSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.696
_cell_length_b   5.696
_cell_length_c   7.285
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   204.686
_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
  K  K0  1  0.333  0.667  0.328  1.0
  K  K1  1  0.000  0.000  0.003  1.0
  Na  Na2  1  0.000  0.000  0.503  1.0
  Na  Na3  1  0.667  0.333  0.703  1.0
  S  S4  1  0.333  0.667  0.771  1.0
  S  S5  1  0.667  0.333  0.233  1.0
  O  O6  1  0.191  0.809  0.699  1.0
  O  O7  1  0.809  0.191  0.305  1.0
  O  O8  1  0.333  0.667  0.973  1.0
  O  O9  1  0.809  0.618  0.305  1.0
  O  O10  1  0.191  0.381  0.699  1.0
  O  O11  1  0.667  0.333  0.030  1.0
  O  O12  1  0.382  0.191  0.305  1.0
  O  O13  1  0.619  0.809  0.699  1.0
[/CIF]
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The material structure described by KNaSO4 crystallizes in the trigonal P3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 10-coordinate geometry to one O(3), three equivalent O(1), and six equivalent O(2) atoms. In the second K site, K(2) is bonded to three equivalent O(1), three equivalent O(2), three equivalent O(3), and three equivalent O(4) atoms to form distorted KO12 cuboctahedra that share edges with six equivalent K(2)O12 cuboctahedra, edges with three equivalent S(1)O4 tetrahedra, edges with three equivalent S(2)O4 tetrahedra, faces with three equivalent Na(2)O7 hexagonal pyramids, and faces with two equivalent Na(1)O6 octahedra. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NaO6 octahedra that share corners with three equivalent S(1)O4 tetrahedra, corners with three equivalent S(2)O4 tetrahedra, edges with three equivalent Na(2)O7 hexagonal pyramids, and faces with two equivalent K(2)O12 cuboctahedra. In the second Na site, Na(2) is bonded to one O(4) and six equivalent O(1) atoms to form distorted NaO7 hexagonal pyramids that share corners with six equivalent Na(2)O7 hexagonal pyramids,  a cornercorner with one S(2)O4 tetrahedra, edges with three equivalent Na(1)O6 octahedra, edges with three equivalent S(1)O4 tetrahedra, and faces with three equivalent K(2)O12 cuboctahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded to one O(3) and three equivalent O(1) atoms to form SO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra, edges with three equivalent K(2)O12 cuboctahedra, and edges with three equivalent Na(2)O7 hexagonal pyramids. The corner-sharing octahedral tilt angles are 17°. In the second S site, S(2) is bonded to one O(4) and three equivalent O(2) atoms to form SO4 tetrahedra that share  a cornercorner with one Na(2)O7 hexagonal pyramid, corners with three equivalent Na(1)O6 octahedra, and edges with three equivalent K(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 17°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), one K(2), one Na(1), two equivalent Na(2), and one S(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one K(2), two equivalent K(1), one Na(1), and one S(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one K(1), three equivalent K(2), and one S(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to three equivalent K(2), one Na(2), and one S(2) atom. is represented by the CIF card [CIF]
data_KNaSO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.696
_cell_length_b   5.696
_cell_length_c   7.285
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   204.686
_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
  K  K0  1  0.333  0.667  0.328  1.0
  K  K1  1  0.000  0.000  0.003  1.0
  Na  Na2  1  0.000  0.000  0.503  1.0
  Na  Na3  1  0.667  0.333  0.703  1.0
  S  S4  1  0.333  0.667  0.771  1.0
  S  S5  1  0.667  0.333  0.233  1.0
  O  O6  1  0.191  0.809  0.699  1.0
  O  O7  1  0.809  0.191  0.305  1.0
  O  O8  1  0.333  0.667  0.973  1.0
  O  O9  1  0.809  0.618  0.305  1.0
  O  O10  1  0.191  0.381  0.699  1.0
  O  O11  1  0.667  0.333  0.030  1.0
  O  O12  1  0.382  0.191  0.305  1.0
  O  O13  1  0.619  0.809  0.699  1.0
[/CIF]
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