The structure described by K3Na(CrO4)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second K site, K(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(2), three equivalent O(1), and three equivalent O(3) atoms. Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-38°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(4) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one Cr(1) atom. In the third O site, O(1) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the fourth O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one Na(1), 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   5.784
_cell_length_b   5.784
_cell_length_c   14.926
_cell_angle_alpha   90.232
_cell_angle_beta   90.232
_cell_angle_gamma   60.134
_symmetry_Int_Tables_number   1
_cell_volume   433.002
_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  0.057  0.943  0.750  1.0
  K  K1  1  0.943  0.057  0.250  1.0
  K  K2  1  0.306  0.350  0.086  1.0
  K  K3  1  0.650  0.694  0.414  1.0
  K  K4  1  0.350  0.306  0.586  1.0
  K  K5  1  0.694  0.650  0.914  1.0
  Na  Na6  1  0.000  1.000  0.500  1.0
  Na  Na7  1  0.000  0.000  0.000  1.0
  Cr  Cr8  1  0.320  0.355  0.365  1.0
  Cr  Cr9  1  0.645  0.680  0.135  1.0
  Cr  Cr10  1  0.680  0.645  0.635  1.0
  Cr  Cr11  1  0.355  0.320  0.865  1.0
  O  O12  1  0.151  0.220  0.408  1.0
  O  O13  1  0.780  0.849  0.092  1.0
  O  O14  1  0.849  0.780  0.592  1.0
  O  O15  1  0.220  0.151  0.908  1.0
  O  O16  1  0.154  0.679  0.384  1.0
  O  O17  1  0.321  0.846  0.116  1.0
  O  O18  1  0.846  0.321  0.616  1.0
  O  O19  1  0.679  0.154  0.884  1.0
  O  O20  1  0.611  0.225  0.417  1.0
  O  O21  1  0.775  0.389  0.083  1.0
  O  O22  1  0.389  0.775  0.583  1.0
  O  O23  1  0.225  0.611  0.917  1.0
  O  O24  1  0.286  0.373  0.759  1.0
  O  O25  1  0.627  0.714  0.741  1.0
  O  O26  1  0.373  0.286  0.259  1.0
  O  O27  1  0.714  0.627  0.241  1.0
[/CIF]
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The structure described by K3Na(CrO4)2 crystallizes in the monoclinic C2/c space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. In the second K site, K(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(2), three equivalent O(1), and three equivalent O(3) atoms. Na(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NaO6 octahedra that share corners with six equivalent Cr(1)O4 tetrahedra. Cr(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form CrO4 tetrahedra that share corners with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-38°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the second O site, O(4) is bonded in a distorted single-bond geometry to one K(1), one K(2), and one Cr(1) atom. In the third O site, O(1) is bonded in a 6-coordinate geometry to one K(1), three equivalent K(2), one Na(1), and one Cr(1) atom. In the fourth O site, O(2) is bonded in a 5-coordinate geometry to one K(1), two equivalent K(2), one Na(1), 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   5.784
_cell_length_b   5.784
_cell_length_c   14.926
_cell_angle_alpha   90.232
_cell_angle_beta   90.232
_cell_angle_gamma   60.134
_symmetry_Int_Tables_number   1
_cell_volume   433.002
_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  0.057  0.943  0.750  1.0
  K  K1  1  0.943  0.057  0.250  1.0
  K  K2  1  0.306  0.350  0.086  1.0
  K  K3  1  0.650  0.694  0.414  1.0
  K  K4  1  0.350  0.306  0.586  1.0
  K  K5  1  0.694  0.650  0.914  1.0
  Na  Na6  1  0.000  1.000  0.500  1.0
  Na  Na7  1  0.000  0.000  0.000  1.0
  Cr  Cr8  1  0.320  0.355  0.365  1.0
  Cr  Cr9  1  0.645  0.680  0.135  1.0
  Cr  Cr10  1  0.680  0.645  0.635  1.0
  Cr  Cr11  1  0.355  0.320  0.865  1.0
  O  O12  1  0.151  0.220  0.408  1.0
  O  O13  1  0.780  0.849  0.092  1.0
  O  O14  1  0.849  0.780  0.592  1.0
  O  O15  1  0.220  0.151  0.908  1.0
  O  O16  1  0.154  0.679  0.384  1.0
  O  O17  1  0.321  0.846  0.116  1.0
  O  O18  1  0.846  0.321  0.616  1.0
  O  O19  1  0.679  0.154  0.884  1.0
  O  O20  1  0.611  0.225  0.417  1.0
  O  O21  1  0.775  0.389  0.083  1.0
  O  O22  1  0.389  0.775  0.583  1.0
  O  O23  1  0.225  0.611  0.917  1.0
  O  O24  1  0.286  0.373  0.759  1.0
  O  O25  1  0.627  0.714  0.741  1.0
  O  O26  1  0.373  0.286  0.259  1.0
  O  O27  1  0.714  0.627  0.241  1.0
[/CIF]
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