The structure described by K3Na(CrO4)2 crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 cuboctahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent Na(1)O6 octahedra. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. Na(1) is bonded to six equivalent O(1) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent K(1)O6 cuboctahedra. Cr(1) is bonded to one O(2) and three equivalent O(1) atoms to form CrO4 tetrahedra that share corners with three equivalent K(1)O6 cuboctahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(2) and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3NaCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.785
_cell_length_b   5.785
_cell_length_c   7.460
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   216.179
_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  0.000  0.000  0.500  1.0
  K  K1  1  0.667  0.333  0.160  1.0
  K  K2  1  0.333  0.667  0.840  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Cr  Cr4  1  0.667  0.333  0.723  1.0
  Cr  Cr5  1  0.333  0.667  0.277  1.0
  O  O6  1  0.359  0.179  0.802  1.0
  O  O7  1  0.821  0.179  0.802  1.0
  O  O8  1  0.821  0.641  0.802  1.0
  O  O9  1  0.179  0.821  0.198  1.0
  O  O10  1  0.641  0.821  0.198  1.0
  O  O11  1  0.179  0.359  0.198  1.0
  O  O12  1  0.333  0.667  0.494  1.0
  O  O13  1  0.667  0.333  0.506  1.0
[/CIF]
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The structure described by K3Na(CrO4)2 crystallizes in the trigonal P-3m1 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent O(1) atoms to form distorted KO6 cuboctahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent Na(1)O6 octahedra. In the second K site, K(2) is bonded in a 10-coordinate geometry to one O(2) and nine equivalent O(1) atoms. Na(1) is bonded to six equivalent O(1) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra and faces with two equivalent K(1)O6 cuboctahedra. Cr(1) is bonded to one O(2) and three equivalent O(1) atoms to form CrO4 tetrahedra that share corners with three equivalent K(1)O6 cuboctahedra and corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one K(2) and one Cr(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K3NaCr2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.785
_cell_length_b   5.785
_cell_length_c   7.460
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   216.179
_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  0.000  0.000  0.500  1.0
  K  K1  1  0.667  0.333  0.160  1.0
  K  K2  1  0.333  0.667  0.840  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Cr  Cr4  1  0.667  0.333  0.723  1.0
  Cr  Cr5  1  0.333  0.667  0.277  1.0
  O  O6  1  0.359  0.179  0.802  1.0
  O  O7  1  0.821  0.179  0.802  1.0
  O  O8  1  0.821  0.641  0.802  1.0
  O  O9  1  0.179  0.821  0.198  1.0
  O  O10  1  0.641  0.821  0.198  1.0
  O  O11  1  0.179  0.359  0.198  1.0
  O  O12  1  0.333  0.667  0.494  1.0
  O  O13  1  0.667  0.333  0.506  1.0
[/CIF]
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