The crystal structure described by Rb3NaMg(MoO4)2 crystallizes in the trigonal P3m1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(4) and six equivalent O(1) atoms to form RbO7 hexagonal pyramids that share corners with six equivalent Rb(1)O7 hexagonal pyramids,  a cornercorner with one Mo(2)O4 tetrahedra, and edges with three equivalent Mo(1)O4 tetrahedra. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to one O(3), three equivalent O(1), and six equivalent O(2) atoms. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one Mg(1) and three equivalent O(2) atoms. Na(1) is bonded in a 3-coordinate geometry to three equivalent O(2) atoms. Mg(1) is bonded in a distorted trigonal planar geometry to one Rb(3) and three equivalent O(1) atoms. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(3) and three equivalent O(1) atoms to form distorted MoO4 tetrahedra that share edges with three equivalent Rb(1)O7 hexagonal pyramids. In the second Mo site, Mo(2) is bonded to one O(4) and three equivalent O(2) atoms to form MoO4 tetrahedra that share  a cornercorner with one Rb(1)O7 hexagonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Rb(2), two equivalent Rb(1), one Mg(1), and one Mo(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Rb(3), two equivalent Rb(2), one Na(1), and one Mo(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(2) and one Mo(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Rb(1) and one Mo(2) atom. is represented by the CIF file [CIF]
data_Rb3NaMg(MoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.269
_cell_length_b   6.269
_cell_length_c   8.942
_cell_angle_alpha   90.000
_cell_angle_beta   89.995
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   304.359
_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  0.667  0.333  0.321  1.0
  Rb  Rb1  1  0.333  0.667  0.628  1.0
  Rb  Rb2  1  1.000  1.000  0.941  1.0
  Na  Na3  1  0.000  0.000  0.577  1.0
  Mg  Mg4  1  0.000  0.000  0.279  1.0
  Mo  Mo5  1  0.333  0.667  0.202  1.0
  Mo  Mo6  1  0.667  0.333  0.781  1.0
  O  O7  1  0.171  0.829  0.311  1.0
  O  O8  1  0.171  0.341  0.311  1.0
  O  O9  1  0.659  0.829  0.311  1.0
  O  O10  1  0.823  0.177  0.709  1.0
  O  O11  1  0.823  0.645  0.709  1.0
  O  O12  1  0.355  0.177  0.709  1.0
  O  O13  1  0.333  0.667  0.998  1.0
  O  O14  1  0.667  0.333  0.979  1.0
[/CIF]
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The crystal structure described by Rb3NaMg(MoO4)2 crystallizes in the trigonal P3m1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded to one O(4) and six equivalent O(1) atoms to form RbO7 hexagonal pyramids that share corners with six equivalent Rb(1)O7 hexagonal pyramids,  a cornercorner with one Mo(2)O4 tetrahedra, and edges with three equivalent Mo(1)O4 tetrahedra. In the second Rb site, Rb(2) is bonded in a 10-coordinate geometry to one O(3), three equivalent O(1), and six equivalent O(2) atoms. In the third Rb site, Rb(3) is bonded in a 4-coordinate geometry to one Mg(1) and three equivalent O(2) atoms. Na(1) is bonded in a 3-coordinate geometry to three equivalent O(2) atoms. Mg(1) is bonded in a distorted trigonal planar geometry to one Rb(3) and three equivalent O(1) atoms. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(3) and three equivalent O(1) atoms to form distorted MoO4 tetrahedra that share edges with three equivalent Rb(1)O7 hexagonal pyramids. In the second Mo site, Mo(2) is bonded to one O(4) and three equivalent O(2) atoms to form MoO4 tetrahedra that share  a cornercorner with one Rb(1)O7 hexagonal pyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Rb(2), two equivalent Rb(1), one Mg(1), and one Mo(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Rb(3), two equivalent Rb(2), one Na(1), and one Mo(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(2) and one Mo(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Rb(1) and one Mo(2) atom. is represented by the CIF file [CIF]
data_Rb3NaMg(MoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.269
_cell_length_b   6.269
_cell_length_c   8.942
_cell_angle_alpha   90.000
_cell_angle_beta   89.995
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   304.359
_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  0.667  0.333  0.321  1.0
  Rb  Rb1  1  0.333  0.667  0.628  1.0
  Rb  Rb2  1  1.000  1.000  0.941  1.0
  Na  Na3  1  0.000  0.000  0.577  1.0
  Mg  Mg4  1  0.000  0.000  0.279  1.0
  Mo  Mo5  1  0.333  0.667  0.202  1.0
  Mo  Mo6  1  0.667  0.333  0.781  1.0
  O  O7  1  0.171  0.829  0.311  1.0
  O  O8  1  0.171  0.341  0.311  1.0
  O  O9  1  0.659  0.829  0.311  1.0
  O  O10  1  0.823  0.177  0.709  1.0
  O  O11  1  0.823  0.645  0.709  1.0
  O  O12  1  0.355  0.177  0.709  1.0
  O  O13  1  0.333  0.667  0.998  1.0
  O  O14  1  0.667  0.333  0.979  1.0
[/CIF]
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