The crystal structure described by K2Na2MgLa2Nb2O10 crystallizes in the monoclinic Pm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted KO8 hexagonal bipyramids that share corners with four equivalent K(1)O8 hexagonal bipyramids,  a cornercorner with one Na(1)O5 trigonal bipyramid,  a cornercorner with one Nb(1)O5 trigonal bipyramid, edges with two equivalent Nb(2)O5 trigonal bipyramids,  a faceface with one Na(1)O5 trigonal bipyramid, and  a faceface with one Nb(1)O5 trigonal bipyramid. In the second K site, K(2) is bonded in a 3-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(6) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(6) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one K(1)O8 hexagonal bipyramid,  a cornercorner with one Nb(1)O5 trigonal bipyramid, corners with four equivalent Nb(2)O5 trigonal bipyramids, and  a faceface with one K(1)O8 hexagonal bipyramid. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. Mg(1) is bonded in a trigonal non-coplanar geometry to one O(2) and two equivalent O(3) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. In the second La site, La(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO5 trigonal bipyramids that share  a cornercorner with one K(1)O8 hexagonal bipyramid,  a cornercorner with one Na(1)O5 trigonal bipyramid, and  a faceface with one K(1)O8 hexagonal bipyramid. In the second Nb site, Nb(2) is bonded to one O(2), two equivalent O(5), and two equivalent O(6) atoms to form NbO5 trigonal bipyramids that share corners with four equivalent Na(1)O5 trigonal bipyramids and edges with two equivalent K(1)O8 hexagonal bipyramids. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Na(1), and one Nb(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 Mg(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one K(1), one Na(2), one Mg(1), one La(1), one La(2), and one Nb(1) atom. In the fourth O site, O(4) is bonded to one Na(2), one La(1), one La(2), and one Nb(1) atom to form edge-sharing ONaLa2Nb tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one La(1), one La(2), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one K(1), one K(2), one Na(1), one La(1), one La(2), and one Nb(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Na2La2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.989
_cell_length_b   5.846
_cell_length_c   8.827
_cell_angle_alpha   90.000
_cell_angle_beta   82.998
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.742
_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  0.240  0.750  0.012  1.0
  K  K1  1  0.854  0.250  0.086  1.0
  Na  Na2  1  0.762  0.750  0.237  1.0
  Na  Na3  1  0.148  0.250  0.717  1.0
  La  La4  1  0.765  0.250  0.481  1.0
  La  La5  1  0.225  0.750  0.483  1.0
  Mg  Mg6  1  0.519  0.250  0.849  1.0
  Nb  Nb7  1  0.716  0.750  0.748  1.0
  Nb  Nb8  1  0.296  0.250  0.268  1.0
  O  O9  1  0.751  0.750  0.956  1.0
  O  O10  1  0.307  0.250  0.040  1.0
  O  O11  1  0.477  0.985  0.710  1.0
  O  O12  1  0.933  0.529  0.636  1.0
  O  O13  1  0.503  0.020  0.338  1.0
  O  O14  1  0.933  0.971  0.636  1.0
  O  O15  1  0.477  0.515  0.710  1.0
  O  O16  1  0.503  0.480  0.338  1.0
  O  O17  1  0.046  0.490  0.303  1.0
  O  O18  1  0.046  0.010  0.303  1.0
[/CIF]
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The crystal structure described by K2Na2MgLa2Nb2O10 crystallizes in the monoclinic Pm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form distorted KO8 hexagonal bipyramids that share corners with four equivalent K(1)O8 hexagonal bipyramids,  a cornercorner with one Na(1)O5 trigonal bipyramid,  a cornercorner with one Nb(1)O5 trigonal bipyramid, edges with two equivalent Nb(2)O5 trigonal bipyramids,  a faceface with one Na(1)O5 trigonal bipyramid, and  a faceface with one Nb(1)O5 trigonal bipyramid. In the second K site, K(2) is bonded in a 3-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(6) atoms. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), two equivalent O(5), and two equivalent O(6) atoms to form distorted NaO5 trigonal bipyramids that share  a cornercorner with one K(1)O8 hexagonal bipyramid,  a cornercorner with one Nb(1)O5 trigonal bipyramid, corners with four equivalent Nb(2)O5 trigonal bipyramids, and  a faceface with one K(1)O8 hexagonal bipyramid. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. Mg(1) is bonded in a trigonal non-coplanar geometry to one O(2) and two equivalent O(3) atoms. There are two inequivalent La sites. In the first La site, La(1) is bonded in a distorted body-centered cubic geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. In the second La site, La(2) is bonded in a distorted body-centered cubic geometry to two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted NbO5 trigonal bipyramids that share  a cornercorner with one K(1)O8 hexagonal bipyramid,  a cornercorner with one Na(1)O5 trigonal bipyramid, and  a faceface with one K(1)O8 hexagonal bipyramid. In the second Nb site, Nb(2) is bonded to one O(2), two equivalent O(5), and two equivalent O(6) atoms to form NbO5 trigonal bipyramids that share corners with four equivalent Na(1)O5 trigonal bipyramids and edges with two equivalent K(1)O8 hexagonal bipyramids. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent K(1), two equivalent K(2), one Na(1), and one Nb(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 Mg(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to one K(1), one Na(2), one Mg(1), one La(1), one La(2), and one Nb(1) atom. In the fourth O site, O(4) is bonded to one Na(2), one La(1), one La(2), and one Nb(1) atom to form edge-sharing ONaLa2Nb tetrahedra. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one La(1), one La(2), and one Nb(2) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one K(1), one K(2), one Na(1), one La(1), one La(2), and one Nb(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_K2Na2La2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.989
_cell_length_b   5.846
_cell_length_c   8.827
_cell_angle_alpha   90.000
_cell_angle_beta   82.998
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   306.742
_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  0.240  0.750  0.012  1.0
  K  K1  1  0.854  0.250  0.086  1.0
  Na  Na2  1  0.762  0.750  0.237  1.0
  Na  Na3  1  0.148  0.250  0.717  1.0
  La  La4  1  0.765  0.250  0.481  1.0
  La  La5  1  0.225  0.750  0.483  1.0
  Mg  Mg6  1  0.519  0.250  0.849  1.0
  Nb  Nb7  1  0.716  0.750  0.748  1.0
  Nb  Nb8  1  0.296  0.250  0.268  1.0
  O  O9  1  0.751  0.750  0.956  1.0
  O  O10  1  0.307  0.250  0.040  1.0
  O  O11  1  0.477  0.985  0.710  1.0
  O  O12  1  0.933  0.529  0.636  1.0
  O  O13  1  0.503  0.020  0.338  1.0
  O  O14  1  0.933  0.971  0.636  1.0
  O  O15  1  0.477  0.515  0.710  1.0
  O  O16  1  0.503  0.480  0.338  1.0
  O  O17  1  0.046  0.490  0.303  1.0
  O  O18  1  0.046  0.010  0.303  1.0
[/CIF]
.