The compound described by Rb4Mg(MoO4)2 crystallizes in the triclinic P1 space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Rb site, Rb(2) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(7) atom. In the third Rb site, Rb(3) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form distorted RbO4 trigonal pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra, corners with two equivalent Mo(1)O4 tetrahedra, and corners with two equivalent Mo(2)O4 tetrahedra. In the fourth Rb site, Rb(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Mg(1) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form MgO4 tetrahedra that share corners with two equivalent Mo(1)O4 tetrahedra,  a cornercorner with one Rb(3)O4 trigonal pyramid, and  an edgeedge with one Mo(2)O4 tetrahedra. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form distorted MoO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and corners with two equivalent Rb(3)O4 trigonal pyramids. In the second Mo site, Mo(2) is bonded to one O(2), one O(3), one O(5), and one O(8) atom to form MoO4 tetrahedra that share corners with two equivalent Rb(3)O4 trigonal pyramids and  an edgeedge with one Mg(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Rb(2), 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(1), one Rb(2), one Rb(3), one Rb(4), and one Mo(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Mo(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Rb(1), one Rb(3), one Rb(4), one Mg(1), and one Mo(1) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(4), one Mg(1), and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Rb(1), one Rb(3), one Rb(4), and one Mo(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Rb(4), and one Mo(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Rb(1), one Mg(1), and one Mo(2) atom. is represented by the CIF file [CIF]
data_Rb4Mg(MoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.839
_cell_length_b   7.700
_cell_length_c   7.874
_cell_angle_alpha   111.140
_cell_angle_beta   97.454
_cell_angle_gamma   116.822
_symmetry_Int_Tables_number   1
_cell_volume   323.145
_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  0.058  0.840  0.263  1.0
  Rb  Rb1  1  0.194  0.334  0.788  1.0
  Rb  Rb2  1  0.487  0.954  0.791  1.0
  Rb  Rb3  1  0.598  0.917  0.257  1.0
  Mg  Mg4  1  0.635  0.407  0.316  1.0
  Mo  Mo5  1  0.127  0.387  0.278  1.0
  Mo  Mo6  1  0.818  0.618  0.735  1.0
  O  O7  1  0.328  0.328  0.153  1.0
  O  O8  1  0.100  0.680  0.872  1.0
  O  O9  1  0.658  0.695  0.885  1.0
  O  O10  1  0.819  0.321  0.161  1.0
  O  O11  1  0.623  0.316  0.527  1.0
  O  O12  1  0.296  0.689  0.403  1.0
  O  O13  1  0.065  0.223  0.406  1.0
  O  O14  1  0.838  0.718  0.541  1.0
[/CIF]
.
The compound described by Rb4Mg(MoO4)2 crystallizes in the triclinic P1 space group. There are four inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 7-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one O(7), and one O(8) atom. In the second Rb site, Rb(2) is bonded in a rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(7) atom. In the third Rb site, Rb(3) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form distorted RbO4 trigonal pyramids that share  a cornercorner with one Mg(1)O4 tetrahedra, corners with two equivalent Mo(1)O4 tetrahedra, and corners with two equivalent Mo(2)O4 tetrahedra. In the fourth Rb site, Rb(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(7) atom. Mg(1) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form MgO4 tetrahedra that share corners with two equivalent Mo(1)O4 tetrahedra,  a cornercorner with one Rb(3)O4 trigonal pyramid, and  an edgeedge with one Mo(2)O4 tetrahedra. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(1), one O(4), one O(6), and one O(7) atom to form distorted MoO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and corners with two equivalent Rb(3)O4 trigonal pyramids. In the second Mo site, Mo(2) is bonded to one O(2), one O(3), one O(5), and one O(8) atom to form MoO4 tetrahedra that share corners with two equivalent Rb(3)O4 trigonal pyramids and  an edgeedge with one Mg(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Rb(2), 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(1), one Rb(2), one Rb(3), one Rb(4), and one Mo(2) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), one Rb(2), one Rb(3), one Rb(4), and one Mo(2) atom. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to one Rb(1), one Rb(3), one Rb(4), one Mg(1), and one Mo(1) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(4), one Mg(1), and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Rb(1), one Rb(3), one Rb(4), and one Mo(1) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Rb(4), and one Mo(1) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Rb(1), one Mg(1), and one Mo(2) atom. is represented by the CIF file [CIF]
data_Rb4Mg(MoO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.839
_cell_length_b   7.700
_cell_length_c   7.874
_cell_angle_alpha   111.140
_cell_angle_beta   97.454
_cell_angle_gamma   116.822
_symmetry_Int_Tables_number   1
_cell_volume   323.145
_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  0.058  0.840  0.263  1.0
  Rb  Rb1  1  0.194  0.334  0.788  1.0
  Rb  Rb2  1  0.487  0.954  0.791  1.0
  Rb  Rb3  1  0.598  0.917  0.257  1.0
  Mg  Mg4  1  0.635  0.407  0.316  1.0
  Mo  Mo5  1  0.127  0.387  0.278  1.0
  Mo  Mo6  1  0.818  0.618  0.735  1.0
  O  O7  1  0.328  0.328  0.153  1.0
  O  O8  1  0.100  0.680  0.872  1.0
  O  O9  1  0.658  0.695  0.885  1.0
  O  O10  1  0.819  0.321  0.161  1.0
  O  O11  1  0.623  0.316  0.527  1.0
  O  O12  1  0.296  0.689  0.403  1.0
  O  O13  1  0.065  0.223  0.406  1.0
  O  O14  1  0.838  0.718  0.541  1.0
[/CIF]
.