The crystal structure described by RbMgFe(SeO4)2 crystallizes in the triclinic P1 space group. Rb(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(7), one O(8), and two equivalent O(6) atoms. Mg(1) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Se(1)O4 tetrahedra and corners with three equivalent Fe(1)O5 trigonal bipyramids. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(7), and one O(8) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Se(1)O4 tetrahedra and corners with three equivalent Mg(1)O4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(5), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Rb(1) and one Se(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), one Fe(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Rb(1), one Mg(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Mg(1), and one Fe(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Rb(1), one Mg(1), one Fe(1), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.273
_cell_length_b   5.767
_cell_length_c   7.512
_cell_angle_alpha   79.966
_cell_angle_beta   101.726
_cell_angle_gamma   127.558
_symmetry_Int_Tables_number   1
_cell_volume   210.500
_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  0.039  0.966  1.0
  Mg  Mg1  1  0.706  0.317  0.238  1.0
  Fe  Fe2  1  0.047  0.948  0.451  1.0
  Se  Se3  1  0.615  0.343  0.737  1.0
  Se  Se4  1  0.402  0.634  0.298  1.0
  O  O5  1  0.704  0.157  0.677  1.0
  O  O6  1  0.786  0.692  0.648  1.0
  O  O7  1  0.281  0.186  0.669  1.0
  O  O8  1  0.758  0.987  0.307  1.0
  O  O9  1  0.307  0.668  0.079  1.0
  O  O10  1  0.652  0.367  0.962  1.0
  O  O11  1  0.017  0.684  0.334  1.0
  O  O12  1  0.401  0.317  0.304  1.0
[/CIF]
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The crystal structure described by RbMgFe(SeO4)2 crystallizes in the triclinic P1 space group. Rb(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), one O(7), one O(8), and two equivalent O(6) atoms. Mg(1) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form MgO4 tetrahedra that share  a cornercorner with one Se(1)O4 tetrahedra and corners with three equivalent Fe(1)O5 trigonal bipyramids. Fe(1) is bonded to one O(2), one O(3), one O(4), one O(7), and one O(8) atom to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Se(1)O4 tetrahedra and corners with three equivalent Mg(1)O4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form SeO4 tetrahedra that share  a cornercorner with one Mg(1)O4 tetrahedra and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to one O(4), one O(5), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Rb(1) and one Se(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Rb(1), one Fe(1), and one Se(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), one Fe(1), and one Se(2) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to one Rb(1) and one Se(2) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Rb(1), one Mg(1), and one Se(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Rb(1), one Mg(1), and one Fe(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Rb(1), one Mg(1), one Fe(1), and one Se(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbMgFe(SeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.273
_cell_length_b   5.767
_cell_length_c   7.512
_cell_angle_alpha   79.966
_cell_angle_beta   101.726
_cell_angle_gamma   127.558
_symmetry_Int_Tables_number   1
_cell_volume   210.500
_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  0.039  0.966  1.0
  Mg  Mg1  1  0.706  0.317  0.238  1.0
  Fe  Fe2  1  0.047  0.948  0.451  1.0
  Se  Se3  1  0.615  0.343  0.737  1.0
  Se  Se4  1  0.402  0.634  0.298  1.0
  O  O5  1  0.704  0.157  0.677  1.0
  O  O6  1  0.786  0.692  0.648  1.0
  O  O7  1  0.281  0.186  0.669  1.0
  O  O8  1  0.758  0.987  0.307  1.0
  O  O9  1  0.307  0.668  0.079  1.0
  O  O10  1  0.652  0.367  0.962  1.0
  O  O11  1  0.017  0.684  0.334  1.0
  O  O12  1  0.401  0.317  0.304  1.0
[/CIF]
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