The structure described by K2Na2MgPr2Nb2O10 crystallizes in the orthorhombic Pmm2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second K site, K(2) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4) and four equivalent O(1) atoms. Mg(1) is bonded in a 4-coordinate geometry to one K(1) and four equivalent O(2) atoms. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 5-coordinate geometry to one O(4) and four equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a distorted trigonal bipyramidal geometry to one O(3) and four equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), one Na(2), one Pr(1), one Pr(2), and one Nb(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Pr(1), one Pr(2), and one Nb(1) atom. In the third O site, O(3) is bonded to two equivalent K(1), two equivalent K(2), one Na(1), and one Nb(2) atom to form distorted corner-sharing OK4NaNb octahedra. The corner-sharing octahedral tilt angles range from 8-21°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Na(2), and one Nb(1) atom. is represented by the CIF file [CIF]
data_K2Na2Pr2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.823
_cell_length_b   5.729
_cell_length_c   9.274
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   309.373
_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  0.750  0.250  0.085  1.0
  K  K1  1  0.250  0.750  0.004  1.0
  Na  Na2  1  0.250  0.250  0.761  1.0
  Na  Na3  1  0.750  0.750  0.236  1.0
  Pr  Pr4  1  0.250  0.750  0.515  1.0
  Pr  Pr5  1  0.750  0.250  0.457  1.0
  Mg  Mg6  1  0.750  0.250  0.752  1.0
  Nb  Nb7  1  0.750  0.750  0.747  1.0
  Nb  Nb8  1  0.250  0.250  0.263  1.0
  O  O9  1  0.481  0.484  0.328  1.0
  O  O10  1  0.526  0.995  0.657  1.0
  O  O11  1  0.481  0.016  0.328  1.0
  O  O12  1  0.526  0.505  0.657  1.0
  O  O13  1  0.019  0.484  0.328  1.0
  O  O14  1  0.250  0.250  0.062  1.0
  O  O15  1  0.750  0.750  0.951  1.0
  O  O16  1  0.019  0.016  0.328  1.0
  O  O17  1  0.974  0.505  0.657  1.0
  O  O18  1  0.974  0.995  0.657  1.0
[/CIF]
.
The structure described by K2Na2MgPr2Nb2O10 crystallizes in the orthorhombic Pmm2 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 9-coordinate geometry to one Mg(1), two equivalent O(3), two equivalent O(4), and four equivalent O(1) atoms. In the second K site, K(2) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 5-coordinate geometry to one O(4) and four equivalent O(1) atoms. Mg(1) is bonded in a 4-coordinate geometry to one K(1) and four equivalent O(2) atoms. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 5-coordinate geometry to one O(4) and four equivalent O(2) atoms. In the second Nb site, Nb(2) is bonded in a distorted trigonal bipyramidal geometry to one O(3) and four equivalent O(1) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one K(1), one Na(2), one Pr(1), one Pr(2), and one Nb(2) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), one Mg(1), one Pr(1), one Pr(2), and one Nb(1) atom. In the third O site, O(3) is bonded to two equivalent K(1), two equivalent K(2), one Na(1), and one Nb(2) atom to form distorted corner-sharing OK4NaNb octahedra. The corner-sharing octahedral tilt angles range from 8-21°. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Na(2), and one Nb(1) atom. is represented by the CIF file [CIF]
data_K2Na2Pr2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.823
_cell_length_b   5.729
_cell_length_c   9.274
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   309.373
_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  0.750  0.250  0.085  1.0
  K  K1  1  0.250  0.750  0.004  1.0
  Na  Na2  1  0.250  0.250  0.761  1.0
  Na  Na3  1  0.750  0.750  0.236  1.0
  Pr  Pr4  1  0.250  0.750  0.515  1.0
  Pr  Pr5  1  0.750  0.250  0.457  1.0
  Mg  Mg6  1  0.750  0.250  0.752  1.0
  Nb  Nb7  1  0.750  0.750  0.747  1.0
  Nb  Nb8  1  0.250  0.250  0.263  1.0
  O  O9  1  0.481  0.484  0.328  1.0
  O  O10  1  0.526  0.995  0.657  1.0
  O  O11  1  0.481  0.016  0.328  1.0
  O  O12  1  0.526  0.505  0.657  1.0
  O  O13  1  0.019  0.484  0.328  1.0
  O  O14  1  0.250  0.250  0.062  1.0
  O  O15  1  0.750  0.750  0.951  1.0
  O  O16  1  0.019  0.016  0.328  1.0
  O  O17  1  0.974  0.505  0.657  1.0
  O  O18  1  0.974  0.995  0.657  1.0
[/CIF]
.