The material structure described by RbK2MgGdV2O8 crystallizes in the monoclinic Cm space group. Rb(1) is bonded in a 8-coordinate geometry to one Mg(1), one O(2), one O(3), one O(6), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(3), and four equivalent O(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Mg(1) is bonded in a distorted trigonal planar geometry to one Rb(1), one O(5), and two equivalent O(1) atoms. Gd(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form GdO6 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(2), one O(6), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Gd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-25°. In the second V site, V(2) is bonded to one O(3), one O(5), and two equivalent O(4) atoms to form VO4 tetrahedra that share corners with three equivalent Gd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-16°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(2), one Mg(1), one Gd(1), and one V(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(1), two equivalent K(2), one Gd(1), and one V(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent K(1), one Gd(1), and one V(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Rb(1), one K(2), two equivalent K(1), one Gd(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one K(2), one Mg(1), and one V(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Rb(1), one K(1), and one V(1) atom. is represented by the CIF file [CIF]
data_K2RbGdMgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.247
_cell_length_b   6.094
_cell_length_c   7.885
_cell_angle_alpha   90.000
_cell_angle_beta   84.577
_cell_angle_gamma   119.194
_symmetry_Int_Tables_number   1
_cell_volume   260.480
_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  0.691  0.346  0.810  1.0
  K  K1  1  0.209  0.604  0.152  1.0
  Rb  Rb2  1  0.121  0.060  0.544  1.0
  Gd  Gd3  1  0.008  0.004  0.988  1.0
  Mg  Mg4  1  0.657  0.829  0.343  1.0
  V  V5  1  0.613  0.306  0.265  1.0
  V  V6  1  0.382  0.691  0.735  1.0
  O  O7  1  0.781  0.127  0.190  1.0
  O  O8  1  0.781  0.653  0.190  1.0
  O  O9  1  0.319  0.159  0.177  1.0
  O  O10  1  0.681  0.840  0.812  1.0
  O  O11  1  0.203  0.368  0.833  1.0
  O  O12  1  0.203  0.835  0.833  1.0
  O  O13  1  0.370  0.685  0.504  1.0
  O  O14  1  0.629  0.314  0.483  1.0
[/CIF]
.
The material structure described by RbK2MgGdV2O8 crystallizes in the monoclinic Cm space group. Rb(1) is bonded in a 8-coordinate geometry to one Mg(1), one O(2), one O(3), one O(6), two equivalent O(4), and two equivalent O(5) atoms. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 7-coordinate geometry to one O(6), two equivalent O(3), and four equivalent O(4) atoms. In the second K site, K(2) is bonded in a 7-coordinate geometry to one O(5), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Mg(1) is bonded in a distorted trigonal planar geometry to one Rb(1), one O(5), and two equivalent O(1) atoms. Gd(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form GdO6 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(2), one O(6), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Gd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-25°. In the second V site, V(2) is bonded to one O(3), one O(5), and two equivalent O(4) atoms to form VO4 tetrahedra that share corners with three equivalent Gd(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-16°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one K(2), one Mg(1), one Gd(1), and one V(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Rb(1), two equivalent K(2), one Gd(1), and one V(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent K(1), one Gd(1), and one V(2) atom. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to one Rb(1), one K(2), two equivalent K(1), one Gd(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to two equivalent Rb(1), one K(2), one Mg(1), and one V(2) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Rb(1), one K(1), and one V(1) atom. is represented by the CIF file [CIF]
data_K2RbGdMgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.247
_cell_length_b   6.094
_cell_length_c   7.885
_cell_angle_alpha   90.000
_cell_angle_beta   84.577
_cell_angle_gamma   119.194
_symmetry_Int_Tables_number   1
_cell_volume   260.480
_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  0.691  0.346  0.810  1.0
  K  K1  1  0.209  0.604  0.152  1.0
  Rb  Rb2  1  0.121  0.060  0.544  1.0
  Gd  Gd3  1  0.008  0.004  0.988  1.0
  Mg  Mg4  1  0.657  0.829  0.343  1.0
  V  V5  1  0.613  0.306  0.265  1.0
  V  V6  1  0.382  0.691  0.735  1.0
  O  O7  1  0.781  0.127  0.190  1.0
  O  O8  1  0.781  0.653  0.190  1.0
  O  O9  1  0.319  0.159  0.177  1.0
  O  O10  1  0.681  0.840  0.812  1.0
  O  O11  1  0.203  0.368  0.833  1.0
  O  O12  1  0.203  0.835  0.833  1.0
  O  O13  1  0.370  0.685  0.504  1.0
  O  O14  1  0.629  0.314  0.483  1.0
[/CIF]
.