The crystal structure described by RbNaMg6O7 crystallizes in the tetragonal P4mm space group. Rb(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(5) atoms. Na(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, edges with four equivalent Mg(1)O5 square pyramids, and edges with four equivalent Mg(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(3) and four equivalent O(4) atoms to form MgO5 square pyramids that share corners with four equivalent Mg(1)O5 square pyramids, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Mg(4)O5 trigonal bipyramids. In the second Mg site, Mg(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(5) atoms. In the third Mg site, Mg(3) is bonded in a square co-planar geometry to one O(4), one O(5), and two equivalent O(1) atoms. In the fourth Mg site, Mg(4) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MgO5 trigonal bipyramids that share corners with four equivalent Mg(4)O5 trigonal bipyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and edges with four equivalent Mg(4)O5 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Na(1) and four equivalent Mg(3) atoms to form ONaMg4 square pyramids that share  a cornercorner with one O(2)RbNaMg4 octahedra, corners with four equivalent O(1)NaMg4 square pyramids, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, and edges with four equivalent O(4)Na2Mg4 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Rb(1), one Na(1), and four equivalent Mg(4) atoms to form distorted ORbNaMg4 octahedra that share corners with four equivalent O(2)RbNaMg4 octahedra,  a cornercorner with one O(1)NaMg4 square pyramid, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, edges with four equivalent O(4)Na2Mg4 octahedra, and edges with four equivalent O(3)Mg5 square pyramids. The corner-sharing octahedral tilt angles are 20°. In the third O site, O(3) is bonded to one Mg(1) and four equivalent Mg(4) atoms to form OMg5 square pyramids that share corners with four equivalent O(3)Mg5 square pyramids, edges with four equivalent O(4)Na2Mg4 octahedra, and edges with four equivalent O(2)RbNaMg4 octahedra. In the fourth O site, O(4) is bonded to two equivalent Na(1), one Mg(3), one Mg(4), and two equivalent Mg(1) atoms to form ONa2Mg4 octahedra that share corners with four equivalent O(4)Na2Mg4 octahedra,  a cornercorner with one O(5)Rb2Mg3 trigonal bipyramid, edges with two equivalent O(2)RbNaMg4 octahedra, edges with four equivalent O(4)Na2Mg4 octahedra, edges with two equivalent O(3)Mg5 square pyramids, and edges with two equivalent O(1)NaMg4 square pyramids. The corner-sharing octahedral tilt angles range from 6-11°. In the fifth O site, O(5) is bonded to two equivalent Rb(1), one Mg(3), and two equivalent Mg(2) atoms to form distorted ORb2Mg3 trigonal bipyramids that share  a cornercorner with one O(4)Na2Mg4 octahedra, corners with two equivalent O(2)RbNaMg4 octahedra, corners with two equivalent O(1)NaMg4 square pyramids, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, and edges with four equivalent O(5)Rb2Mg3 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 0-51°. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbNaMg6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.244
_cell_length_b   4.244
_cell_length_c   11.407
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   205.480
_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  0.000  0.000  0.542  1.0
  Na  Na1  1  0.000  0.000  0.017  1.0
  Mg  Mg2  1  0.500  0.500  0.008  1.0
  Mg  Mg3  1  0.500  0.500  0.404  1.0
  Mg  Mg4  1  0.000  0.500  0.214  1.0
  Mg  Mg5  1  0.000  0.500  0.836  1.0
  Mg  Mg6  1  0.500  0.000  0.214  1.0
  Mg  Mg7  1  0.500  0.000  0.836  1.0
  O  O8  1  0.000  0.000  0.211  1.0
  O  O9  1  0.000  0.000  0.804  1.0
  O  O10  1  0.500  0.500  0.828  1.0
  O  O11  1  0.000  0.500  0.027  1.0
  O  O12  1  0.000  0.500  0.391  1.0
  O  O13  1  0.500  0.000  0.027  1.0
  O  O14  1  0.500  0.000  0.391  1.0
[/CIF]
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The crystal structure described by RbNaMg6O7 crystallizes in the tetragonal P4mm space group. Rb(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(5) atoms. Na(1) is bonded to one O(1), one O(2), and four equivalent O(4) atoms to form NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, edges with four equivalent Mg(1)O5 square pyramids, and edges with four equivalent Mg(4)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(3) and four equivalent O(4) atoms to form MgO5 square pyramids that share corners with four equivalent Mg(1)O5 square pyramids, edges with four equivalent Na(1)O6 octahedra, and edges with four equivalent Mg(4)O5 trigonal bipyramids. In the second Mg site, Mg(2) is bonded in a rectangular see-saw-like geometry to four equivalent O(5) atoms. In the third Mg site, Mg(3) is bonded in a square co-planar geometry to one O(4), one O(5), and two equivalent O(1) atoms. In the fourth Mg site, Mg(4) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MgO5 trigonal bipyramids that share corners with four equivalent Mg(4)O5 trigonal bipyramids, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Mg(1)O5 square pyramids, and edges with four equivalent Mg(4)O5 trigonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Na(1) and four equivalent Mg(3) atoms to form ONaMg4 square pyramids that share  a cornercorner with one O(2)RbNaMg4 octahedra, corners with four equivalent O(1)NaMg4 square pyramids, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, and edges with four equivalent O(4)Na2Mg4 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to one Rb(1), one Na(1), and four equivalent Mg(4) atoms to form distorted ORbNaMg4 octahedra that share corners with four equivalent O(2)RbNaMg4 octahedra,  a cornercorner with one O(1)NaMg4 square pyramid, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, edges with four equivalent O(4)Na2Mg4 octahedra, and edges with four equivalent O(3)Mg5 square pyramids. The corner-sharing octahedral tilt angles are 20°. In the third O site, O(3) is bonded to one Mg(1) and four equivalent Mg(4) atoms to form OMg5 square pyramids that share corners with four equivalent O(3)Mg5 square pyramids, edges with four equivalent O(4)Na2Mg4 octahedra, and edges with four equivalent O(2)RbNaMg4 octahedra. In the fourth O site, O(4) is bonded to two equivalent Na(1), one Mg(3), one Mg(4), and two equivalent Mg(1) atoms to form ONa2Mg4 octahedra that share corners with four equivalent O(4)Na2Mg4 octahedra,  a cornercorner with one O(5)Rb2Mg3 trigonal bipyramid, edges with two equivalent O(2)RbNaMg4 octahedra, edges with four equivalent O(4)Na2Mg4 octahedra, edges with two equivalent O(3)Mg5 square pyramids, and edges with two equivalent O(1)NaMg4 square pyramids. The corner-sharing octahedral tilt angles range from 6-11°. In the fifth O site, O(5) is bonded to two equivalent Rb(1), one Mg(3), and two equivalent Mg(2) atoms to form distorted ORb2Mg3 trigonal bipyramids that share  a cornercorner with one O(4)Na2Mg4 octahedra, corners with two equivalent O(2)RbNaMg4 octahedra, corners with two equivalent O(1)NaMg4 square pyramids, corners with four equivalent O(5)Rb2Mg3 trigonal bipyramids, and edges with four equivalent O(5)Rb2Mg3 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 0-51°. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbNaMg6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.244
_cell_length_b   4.244
_cell_length_c   11.407
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   205.480
_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  0.000  0.000  0.542  1.0
  Na  Na1  1  0.000  0.000  0.017  1.0
  Mg  Mg2  1  0.500  0.500  0.008  1.0
  Mg  Mg3  1  0.500  0.500  0.404  1.0
  Mg  Mg4  1  0.000  0.500  0.214  1.0
  Mg  Mg5  1  0.000  0.500  0.836  1.0
  Mg  Mg6  1  0.500  0.000  0.214  1.0
  Mg  Mg7  1  0.500  0.000  0.836  1.0
  O  O8  1  0.000  0.000  0.211  1.0
  O  O9  1  0.000  0.000  0.804  1.0
  O  O10  1  0.500  0.500  0.828  1.0
  O  O11  1  0.000  0.500  0.027  1.0
  O  O12  1  0.000  0.500  0.391  1.0
  O  O13  1  0.500  0.000  0.027  1.0
  O  O14  1  0.500  0.000  0.391  1.0
[/CIF]
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