The crystal structure described by Rb2Ba8Mg(Sb3O)2 crystallizes in the orthorhombic Fmm2 space group. Rb(1) is bonded in a 7-coordinate geometry to one Mg(1), one Sb(2), one Sb(3), two equivalent Sb(1), and two equivalent Sb(4) atoms. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted single-bond geometry to one Sb(2), one Sb(3), two equivalent Sb(4), and one O(1) atom. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Sb(4), and one O(1) atom. In the third Ba site, Ba(3) is bonded in a distorted single-bond geometry to one Sb(2), two equivalent Sb(4), and one O(1) atom. Mg(1) is bonded to two equivalent Rb(1), two equivalent Ba(2), one Sb(3), and two equivalent Sb(1) atoms to form distorted MgRb2Ba2Sb3 pentagonal bipyramids that share corners with two equivalent O(1)Ba4 tetrahedra. There are four inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 1-coordinate geometry to two equivalent Rb(1) and one Mg(1) atom. In the second Sb site, Sb(2) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Ba(3), and four equivalent Ba(1) atoms. In the third Sb site, Sb(3) is bonded in a 7-coordinate geometry to two equivalent Rb(1), four equivalent Ba(1), and one Mg(1) atom. In the fourth Sb site, Sb(4) is bonded in a 10-coordinate geometry to two equivalent Rb(1), two equivalent Ba(2), two equivalent Ba(3), and four equivalent Ba(1) atoms. O(1) is bonded to one Ba(2), one Ba(3), and two equivalent Ba(1) atoms to form OBa4 tetrahedra that share  a cornercorner with one Mg(1)Rb2Ba2Sb3 pentagonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2Ba8Mg(Sb3O)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.345
_cell_length_b   9.345
_cell_length_c   10.871
_cell_angle_alpha   117.123
_cell_angle_beta   117.123
_cell_angle_gamma   86.525
_symmetry_Int_Tables_number   1
_cell_volume   738.982
_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  0.998  0.013  0.000  1.0
  Rb  Rb1  1  0.513  0.498  0.000  1.0
  Ba  Ba2  1  0.506  0.699  0.714  1.0
  Ba  Ba3  1  0.199  0.006  0.714  1.0
  Ba  Ba4  1  0.792  0.986  0.286  1.0
  Ba  Ba5  1  0.964  0.464  0.625  1.0
  Ba  Ba6  1  0.486  0.292  0.286  1.0
  Ba  Ba7  1  0.700  0.200  0.696  1.0
  Ba  Ba8  1  0.004  0.504  0.304  1.0
  Ba  Ba9  1  0.339  0.839  0.375  1.0
  Mg  Mg10  1  0.177  0.677  0.000  1.0
  Sb  Sb11  1  0.889  0.621  0.000  1.0
  Sb  Sb12  1  0.641  0.141  0.000  1.0
  Sb  Sb13  1  0.121  0.389  0.000  1.0
  Sb  Sb14  1  0.372  0.872  0.000  1.0
  Sb  Sb15  1  0.252  0.252  0.500  1.0
  Sb  Sb16  1  0.752  0.752  0.500  1.0
  O  O17  1  0.734  0.234  0.481  1.0
  O  O18  1  0.253  0.753  0.519  1.0
[/CIF]
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The crystal structure described by Rb2Ba8Mg(Sb3O)2 crystallizes in the orthorhombic Fmm2 space group. Rb(1) is bonded in a 7-coordinate geometry to one Mg(1), one Sb(2), one Sb(3), two equivalent Sb(1), and two equivalent Sb(4) atoms. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted single-bond geometry to one Sb(2), one Sb(3), two equivalent Sb(4), and one O(1) atom. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one Mg(1), two equivalent Sb(4), and one O(1) atom. In the third Ba site, Ba(3) is bonded in a distorted single-bond geometry to one Sb(2), two equivalent Sb(4), and one O(1) atom. Mg(1) is bonded to two equivalent Rb(1), two equivalent Ba(2), one Sb(3), and two equivalent Sb(1) atoms to form distorted MgRb2Ba2Sb3 pentagonal bipyramids that share corners with two equivalent O(1)Ba4 tetrahedra. There are four inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 1-coordinate geometry to two equivalent Rb(1) and one Mg(1) atom. In the second Sb site, Sb(2) is bonded in a 8-coordinate geometry to two equivalent Rb(1), two equivalent Ba(3), and four equivalent Ba(1) atoms. In the third Sb site, Sb(3) is bonded in a 7-coordinate geometry to two equivalent Rb(1), four equivalent Ba(1), and one Mg(1) atom. In the fourth Sb site, Sb(4) is bonded in a 10-coordinate geometry to two equivalent Rb(1), two equivalent Ba(2), two equivalent Ba(3), and four equivalent Ba(1) atoms. O(1) is bonded to one Ba(2), one Ba(3), and two equivalent Ba(1) atoms to form OBa4 tetrahedra that share  a cornercorner with one Mg(1)Rb2Ba2Sb3 pentagonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb2Ba8Mg(Sb3O)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.345
_cell_length_b   9.345
_cell_length_c   10.871
_cell_angle_alpha   117.123
_cell_angle_beta   117.123
_cell_angle_gamma   86.525
_symmetry_Int_Tables_number   1
_cell_volume   738.982
_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  0.998  0.013  0.000  1.0
  Rb  Rb1  1  0.513  0.498  0.000  1.0
  Ba  Ba2  1  0.506  0.699  0.714  1.0
  Ba  Ba3  1  0.199  0.006  0.714  1.0
  Ba  Ba4  1  0.792  0.986  0.286  1.0
  Ba  Ba5  1  0.964  0.464  0.625  1.0
  Ba  Ba6  1  0.486  0.292  0.286  1.0
  Ba  Ba7  1  0.700  0.200  0.696  1.0
  Ba  Ba8  1  0.004  0.504  0.304  1.0
  Ba  Ba9  1  0.339  0.839  0.375  1.0
  Mg  Mg10  1  0.177  0.677  0.000  1.0
  Sb  Sb11  1  0.889  0.621  0.000  1.0
  Sb  Sb12  1  0.641  0.141  0.000  1.0
  Sb  Sb13  1  0.121  0.389  0.000  1.0
  Sb  Sb14  1  0.372  0.872  0.000  1.0
  Sb  Sb15  1  0.252  0.252  0.500  1.0
  Sb  Sb16  1  0.752  0.752  0.500  1.0
  O  O17  1  0.734  0.234  0.481  1.0
  O  O18  1  0.253  0.753  0.519  1.0
[/CIF]
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