The compound described by RbK2MgTbV2O8 crystallizes in the trigonal P3m1 space group. Rb(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent O(2), and three equivalent O(3) atoms. There are two inequivalent K sites. In the first K site, K(1) is bonded in a distorted single-bond geometry to one O(4) atom. In the second K site, K(2) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Rb(1) and three equivalent O(1) atoms. Tb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TbO6 octahedra that share corners with three equivalent V(1)O4 tetrahedra and corners with three equivalent V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(4) and three equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 22°. In the second V site, V(2) is bonded to one O(3) and three equivalent O(2) atoms to form VO4 tetrahedra that share corners with three equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one Mg(1), one Tb(1), and one V(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(1), one Tb(1), and one V(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to three equivalent Rb(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one K(1) and one V(1) atom. is represented by the CIF card [CIF]
data_K2RbTbMgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   5.959
_cell_length_c   9.559
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   293.954
_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
  K  K0  1  0.667  0.333  0.707  1.0
  K  K1  1  0.333  0.667  0.148  1.0
  Rb  Rb2  1  0.000  0.000  0.601  1.0
  Tb  Tb3  1  0.000  0.000  0.987  1.0
  Mg  Mg4  1  0.000  0.000  0.270  1.0
  V  V5  1  0.667  0.333  0.241  1.0
  V  V6  1  0.333  0.667  0.778  1.0
  O  O7  1  0.841  0.159  0.160  1.0
  O  O8  1  0.841  0.682  0.160  1.0
  O  O9  1  0.318  0.159  0.160  1.0
  O  O10  1  0.657  0.828  0.837  1.0
  O  O11  1  0.172  0.343  0.837  1.0
  O  O12  1  0.172  0.828  0.837  1.0
  O  O13  1  0.333  0.667  0.602  1.0
  O  O14  1  0.667  0.333  0.431  1.0
[/CIF]
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The compound described by RbK2MgTbV2O8 crystallizes in the trigonal P3m1 space group. Rb(1) is bonded in a 7-coordinate geometry to one Mg(1), three equivalent O(2), and three equivalent O(3) atoms. There are two inequivalent K sites. In the first K site, K(1) is bonded in a distorted single-bond geometry to one O(4) atom. In the second K site, K(2) is bonded in a distorted hexagonal planar geometry to six equivalent O(1) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Rb(1) and three equivalent O(1) atoms. Tb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TbO6 octahedra that share corners with three equivalent V(1)O4 tetrahedra and corners with three equivalent V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(4) and three equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 22°. In the second V site, V(2) is bonded to one O(3) and three equivalent O(2) atoms to form VO4 tetrahedra that share corners with three equivalent Tb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to two equivalent K(2), one Mg(1), one Tb(1), and one V(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(1), one Tb(1), and one V(2) atom. In the third O site, O(3) is bonded in a single-bond geometry to three equivalent Rb(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a linear geometry to one K(1) and one V(1) atom. is represented by the CIF card [CIF]
data_K2RbTbMgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.959
_cell_length_b   5.959
_cell_length_c   9.559
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   293.954
_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
  K  K0  1  0.667  0.333  0.707  1.0
  K  K1  1  0.333  0.667  0.148  1.0
  Rb  Rb2  1  0.000  0.000  0.601  1.0
  Tb  Tb3  1  0.000  0.000  0.987  1.0
  Mg  Mg4  1  0.000  0.000  0.270  1.0
  V  V5  1  0.667  0.333  0.241  1.0
  V  V6  1  0.333  0.667  0.778  1.0
  O  O7  1  0.841  0.159  0.160  1.0
  O  O8  1  0.841  0.682  0.160  1.0
  O  O9  1  0.318  0.159  0.160  1.0
  O  O10  1  0.657  0.828  0.837  1.0
  O  O11  1  0.172  0.343  0.837  1.0
  O  O12  1  0.172  0.828  0.837  1.0
  O  O13  1  0.333  0.667  0.602  1.0
  O  O14  1  0.667  0.333  0.431  1.0
[/CIF]
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