The material described by Rb3NaMg(WO4)2 crystallizes in the trigonal P3m1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to one Mg(1) and three equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded to one O(3) and six equivalent O(2) atoms to form RbO7 hexagonal pyramids that share corners with six equivalent Rb(2)O7 hexagonal pyramids,  a cornercorner with one W(1)O4 tetrahedra, and edges with three equivalent W(2)O4 tetrahedra. In the third Rb site, Rb(3) is bonded in a 10-coordinate geometry to one O(4), three equivalent O(2), and six equivalent O(1) atoms. Na(1) is bonded in a 3-coordinate geometry to three equivalent O(1) atoms. Mg(1) is bonded in a trigonal planar geometry to one Rb(1) and three equivalent O(2) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(3) and three equivalent O(1) atoms to form WO4 tetrahedra that share  a cornercorner with one Rb(2)O7 hexagonal pyramid. In the second W site, W(2) is bonded to one O(4) and three equivalent O(2) atoms to form distorted WO4 tetrahedra that share edges with three equivalent Rb(2)O7 hexagonal pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(3), one Na(1), and one W(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(3), two equivalent Rb(2), one Mg(1), and one W(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Rb(2) and one W(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Rb(3) and one W(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3NaMg(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.294
_cell_length_b   6.295
_cell_length_c   8.875
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.003
_symmetry_Int_Tables_number   1
_cell_volume   304.503
_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  0.444  1.0
  Rb  Rb1  1  0.333  0.667  0.819  1.0
  Rb  Rb2  1  0.667  0.333  0.140  1.0
  Na  Na3  1  0.000  0.000  0.080  1.0
  Mg  Mg4  1  0.000  0.000  0.780  1.0
  W  W5  1  0.333  0.667  0.285  1.0
  W  W6  1  0.667  0.333  0.697  1.0
  O  O7  1  0.177  0.823  0.211  1.0
  O  O8  1  0.177  0.354  0.211  1.0
  O  O9  1  0.646  0.823  0.211  1.0
  O  O10  1  0.829  0.171  0.808  1.0
  O  O11  1  0.829  0.659  0.808  1.0
  O  O12  1  0.341  0.171  0.808  1.0
  O  O13  1  0.333  0.667  0.487  1.0
  O  O14  1  0.667  0.333  0.486  1.0
[/CIF]
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The material described by Rb3NaMg(WO4)2 crystallizes in the trigonal P3m1 space group. There are three inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 4-coordinate geometry to one Mg(1) and three equivalent O(1) atoms. In the second Rb site, Rb(2) is bonded to one O(3) and six equivalent O(2) atoms to form RbO7 hexagonal pyramids that share corners with six equivalent Rb(2)O7 hexagonal pyramids,  a cornercorner with one W(1)O4 tetrahedra, and edges with three equivalent W(2)O4 tetrahedra. In the third Rb site, Rb(3) is bonded in a 10-coordinate geometry to one O(4), three equivalent O(2), and six equivalent O(1) atoms. Na(1) is bonded in a 3-coordinate geometry to three equivalent O(1) atoms. Mg(1) is bonded in a trigonal planar geometry to one Rb(1) and three equivalent O(2) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(3) and three equivalent O(1) atoms to form WO4 tetrahedra that share  a cornercorner with one Rb(2)O7 hexagonal pyramid. In the second W site, W(2) is bonded to one O(4) and three equivalent O(2) atoms to form distorted WO4 tetrahedra that share edges with three equivalent Rb(2)O7 hexagonal pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(3), one Na(1), and one W(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(3), two equivalent Rb(2), one Mg(1), and one W(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Rb(2) and one W(1) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Rb(3) and one W(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3NaMg(WO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.294
_cell_length_b   6.295
_cell_length_c   8.875
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.003
_symmetry_Int_Tables_number   1
_cell_volume   304.503
_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  0.444  1.0
  Rb  Rb1  1  0.333  0.667  0.819  1.0
  Rb  Rb2  1  0.667  0.333  0.140  1.0
  Na  Na3  1  0.000  0.000  0.080  1.0
  Mg  Mg4  1  0.000  0.000  0.780  1.0
  W  W5  1  0.333  0.667  0.285  1.0
  W  W6  1  0.667  0.333  0.697  1.0
  O  O7  1  0.177  0.823  0.211  1.0
  O  O8  1  0.177  0.354  0.211  1.0
  O  O9  1  0.646  0.823  0.211  1.0
  O  O10  1  0.829  0.171  0.808  1.0
  O  O11  1  0.829  0.659  0.808  1.0
  O  O12  1  0.341  0.171  0.808  1.0
  O  O13  1  0.333  0.667  0.487  1.0
  O  O14  1  0.667  0.333  0.486  1.0
[/CIF]
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