The material described by K2Na2MgSm2Nb2O10 crystallizes in the monoclinic Pm 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(1), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), two equivalent O(5), 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(3), and two equivalent O(5) atoms to form distorted NaO5 trigonal bipyramids that share corners with four equivalent Nb(1)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. Mg(1) is bonded in a trigonal non-coplanar geometry to one K(1), one O(6), and two equivalent O(4) atoms. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(6), two equivalent O(3), and two equivalent O(5) atoms to form distorted NbO5 trigonal bipyramids that share corners with four equivalent Na(1)O5 trigonal bipyramids. In the second Nb site, Nb(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(4) atoms. 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(2) atom. In the second O site, O(2) is bonded to one Na(2), one Sm(1), one Sm(2), and one Nb(2) atom to form edge-sharing ONaSm2Nb tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(1), one Na(1), one Sm(1), one Sm(2), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one K(2), one Na(2), one Mg(1), one Sm(1), one Sm(2), and one Nb(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one K(1), one K(2), one Na(1), one Sm(1), one Sm(2), and one Nb(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), two equivalent K(2), one Mg(1), and one Nb(1) atom. is represented by the CIF file [CIF]
data_K2Na2Sm2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.730
_cell_length_b   5.874
_cell_length_c   8.728
_cell_angle_alpha   85.003
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.648
_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  0.250  0.819  0.096  1.0
  K  K1  1  0.750  0.246  0.004  1.0
  Na  Na2  1  0.750  0.765  0.247  1.0
  Na  Na3  1  0.250  0.119  0.744  1.0
  Sm  Sm4  1  0.750  0.245  0.506  1.0
  Sm  Sm5  1  0.250  0.756  0.486  1.0
  Mg  Mg6  1  0.250  0.540  0.830  1.0
  Nb  Nb7  1  0.250  0.288  0.259  1.0
  Nb  Nb8  1  0.750  0.725  0.748  1.0
  O  O9  1  0.750  0.761  0.960  1.0
  O  O10  1  0.527  0.943  0.622  1.0
  O  O11  1  0.020  0.498  0.343  1.0
  O  O12  1  0.516  0.463  0.691  1.0
  O  O13  1  0.984  0.463  0.691  1.0
  O  O14  1  0.973  0.943  0.622  1.0
  O  O15  1  0.020  0.045  0.310  1.0
  O  O16  1  0.480  0.498  0.343  1.0
  O  O17  1  0.250  0.339  0.037  1.0
  O  O18  1  0.480  0.045  0.310  1.0
[/CIF]
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The material described by K2Na2MgSm2Nb2O10 crystallizes in the monoclinic Pm 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(1), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. In the second K site, K(2) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(4), two equivalent O(5), 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(3), and two equivalent O(5) atoms to form distorted NaO5 trigonal bipyramids that share corners with four equivalent Nb(1)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. Mg(1) is bonded in a trigonal non-coplanar geometry to one K(1), one O(6), and two equivalent O(4) atoms. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded in a body-centered cubic geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. In the second Sm site, Sm(2) is bonded in a 8-coordinate geometry to two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(6), two equivalent O(3), and two equivalent O(5) atoms to form distorted NbO5 trigonal bipyramids that share corners with four equivalent Na(1)O5 trigonal bipyramids. In the second Nb site, Nb(2) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(4) atoms. 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(2) atom. In the second O site, O(2) is bonded to one Na(2), one Sm(1), one Sm(2), and one Nb(2) atom to form edge-sharing ONaSm2Nb tetrahedra. In the third O site, O(3) is bonded in a 5-coordinate geometry to one K(1), one Na(1), one Sm(1), one Sm(2), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one K(2), one Na(2), one Mg(1), one Sm(1), one Sm(2), and one Nb(2) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one K(1), one K(2), one Na(1), one Sm(1), one Sm(2), and one Nb(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), two equivalent K(2), one Mg(1), and one Nb(1) atom. is represented by the CIF file [CIF]
data_K2Na2Sm2MgNb2O10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.730
_cell_length_b   5.874
_cell_length_c   8.728
_cell_angle_alpha   85.003
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   292.648
_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  0.250  0.819  0.096  1.0
  K  K1  1  0.750  0.246  0.004  1.0
  Na  Na2  1  0.750  0.765  0.247  1.0
  Na  Na3  1  0.250  0.119  0.744  1.0
  Sm  Sm4  1  0.750  0.245  0.506  1.0
  Sm  Sm5  1  0.250  0.756  0.486  1.0
  Mg  Mg6  1  0.250  0.540  0.830  1.0
  Nb  Nb7  1  0.250  0.288  0.259  1.0
  Nb  Nb8  1  0.750  0.725  0.748  1.0
  O  O9  1  0.750  0.761  0.960  1.0
  O  O10  1  0.527  0.943  0.622  1.0
  O  O11  1  0.020  0.498  0.343  1.0
  O  O12  1  0.516  0.463  0.691  1.0
  O  O13  1  0.984  0.463  0.691  1.0
  O  O14  1  0.973  0.943  0.622  1.0
  O  O15  1  0.020  0.045  0.310  1.0
  O  O16  1  0.480  0.498  0.343  1.0
  O  O17  1  0.250  0.339  0.037  1.0
  O  O18  1  0.480  0.045  0.310  1.0
[/CIF]
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