The crystal structure described by RbCa2NaNb4O13 crystallizes in the tetragonal P4/mmm space group. Rb(1) is bonded in a body-centered cubic geometry to eight equivalent O(4) atoms. Na(1) is bonded to four equivalent O(5) and eight equivalent O(2) atoms to form NaO12 cuboctahedra that share corners with four equivalent Na(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, faces with two equivalent Ca(1)O12 cuboctahedra, faces with four equivalent Na(1)O12 cuboctahedra, and faces with eight equivalent Nb(2)O6 octahedra. Ca(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form distorted CaO12 cuboctahedra that share corners with four equivalent Na(1)O12 cuboctahedra, corners with four equivalent Ca(1)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra, faces with four equivalent Ca(1)O12 cuboctahedra, and faces with four equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), and four equivalent O(1) atoms. In the second Nb site, Nb(2) is bonded to one O(3), one O(5), and four equivalent O(2) atoms to form NbO6 octahedra that share corners with five equivalent Nb(2)O6 octahedra, faces with four equivalent Na(1)O12 cuboctahedra, and faces with four equivalent Ca(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and two equivalent Nb(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Nb2 trigonal pyramids. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Na(1), two equivalent Ca(1), and two equivalent Nb(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ca(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to four equivalent Rb(1) and one Nb(1) atom. In the fifth O site, O(5) is bonded to four equivalent Na(1) and two equivalent Nb(2) atoms to form a mixture of distorted corner and edge-sharing ONa4Nb2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbNaCa2Nb4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.979
_cell_length_b   3.979
_cell_length_c   19.254
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   304.865
_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
  Rb  Rb0  1  0.500  0.500  0.500  1.0
  Na  Na1  1  0.500  0.500  0.000  1.0
  Ca  Ca2  1  0.500  0.500  0.778  1.0
  Ca  Ca3  1  0.500  0.500  0.222  1.0
  Nb  Nb4  1  0.000  0.000  0.673  1.0
  Nb  Nb5  1  0.000  0.000  0.327  1.0
  Nb  Nb6  1  0.000  0.000  0.895  1.0
  Nb  Nb7  1  0.000  0.000  0.105  1.0
  O  O8  1  0.500  0.000  0.695  1.0
  O  O9  1  0.000  0.500  0.695  1.0
  O  O10  1  0.500  0.000  0.305  1.0
  O  O11  1  0.000  0.500  0.305  1.0
  O  O12  1  0.500  0.000  0.895  1.0
  O  O13  1  0.000  0.500  0.895  1.0
  O  O14  1  0.500  0.000  0.105  1.0
  O  O15  1  0.000  0.500  0.105  1.0
  O  O16  1  0.000  0.000  0.793  1.0
  O  O17  1  0.000  0.000  0.207  1.0
  O  O18  1  0.000  0.000  0.579  1.0
  O  O19  1  0.000  0.000  0.421  1.0
  O  O20  1  0.000  0.000  0.000  1.0
[/CIF]
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The crystal structure described by RbCa2NaNb4O13 crystallizes in the tetragonal P4/mmm space group. Rb(1) is bonded in a body-centered cubic geometry to eight equivalent O(4) atoms. Na(1) is bonded to four equivalent O(5) and eight equivalent O(2) atoms to form NaO12 cuboctahedra that share corners with four equivalent Na(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, faces with two equivalent Ca(1)O12 cuboctahedra, faces with four equivalent Na(1)O12 cuboctahedra, and faces with eight equivalent Nb(2)O6 octahedra. Ca(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form distorted CaO12 cuboctahedra that share corners with four equivalent Na(1)O12 cuboctahedra, corners with four equivalent Ca(1)O12 cuboctahedra,  a faceface with one Na(1)O12 cuboctahedra, faces with four equivalent Ca(1)O12 cuboctahedra, and faces with four equivalent Nb(2)O6 octahedra. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), and four equivalent O(1) atoms. In the second Nb site, Nb(2) is bonded to one O(3), one O(5), and four equivalent O(2) atoms to form NbO6 octahedra that share corners with five equivalent Nb(2)O6 octahedra, faces with four equivalent Na(1)O12 cuboctahedra, and faces with four equivalent Ca(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and two equivalent Nb(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Nb2 trigonal pyramids. In the second O site, O(2) is bonded in a distorted linear geometry to two equivalent Na(1), two equivalent Ca(1), and two equivalent Nb(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Ca(1), one Nb(1), and one Nb(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to four equivalent Rb(1) and one Nb(1) atom. In the fifth O site, O(5) is bonded to four equivalent Na(1) and two equivalent Nb(2) atoms to form a mixture of distorted corner and edge-sharing ONa4Nb2 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbNaCa2Nb4O13
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.979
_cell_length_b   3.979
_cell_length_c   19.254
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   304.865
_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
  Rb  Rb0  1  0.500  0.500  0.500  1.0
  Na  Na1  1  0.500  0.500  0.000  1.0
  Ca  Ca2  1  0.500  0.500  0.778  1.0
  Ca  Ca3  1  0.500  0.500  0.222  1.0
  Nb  Nb4  1  0.000  0.000  0.673  1.0
  Nb  Nb5  1  0.000  0.000  0.327  1.0
  Nb  Nb6  1  0.000  0.000  0.895  1.0
  Nb  Nb7  1  0.000  0.000  0.105  1.0
  O  O8  1  0.500  0.000  0.695  1.0
  O  O9  1  0.000  0.500  0.695  1.0
  O  O10  1  0.500  0.000  0.305  1.0
  O  O11  1  0.000  0.500  0.305  1.0
  O  O12  1  0.500  0.000  0.895  1.0
  O  O13  1  0.000  0.500  0.895  1.0
  O  O14  1  0.500  0.000  0.105  1.0
  O  O15  1  0.000  0.500  0.105  1.0
  O  O16  1  0.000  0.000  0.793  1.0
  O  O17  1  0.000  0.000  0.207  1.0
  O  O18  1  0.000  0.000  0.579  1.0
  O  O19  1  0.000  0.000  0.421  1.0
  O  O20  1  0.000  0.000  0.000  1.0
[/CIF]
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