The material described by MgTb2V2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent V(1)O4 tetrahedra and edges with two equivalent V(1)O4 tetrahedra. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. V(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Tb(1), and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Tb(1) and one V(1) atom. In the third O site, O(3) is bonded to one Mg(1), two equivalent Tb(1), and one V(1) atom to form distorted corner-sharing OTb2MgV trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Tb(1), and one V(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2MgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.056
_cell_length_b   6.218
_cell_length_c   6.056
_cell_angle_alpha   105.508
_cell_angle_beta   105.910
_cell_angle_gamma   116.079
_symmetry_Int_Tables_number   1
_cell_volume   175.997
_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
  Tb  Tb0  1  0.153  0.912  0.296  1.0
  Tb  Tb1  1  0.884  0.088  0.741  1.0
  Mg  Mg2  1  0.736  0.500  0.736  1.0
  V  V3  1  0.356  0.646  0.758  1.0
  V  V4  1  0.612  0.354  0.210  1.0
  O  O5  1  0.830  0.712  0.465  1.0
  O  O6  1  0.391  0.803  0.555  1.0
  O  O7  1  0.738  0.805  0.946  1.0
  O  O8  1  0.775  0.354  0.005  1.0
  O  O9  1  0.641  0.195  0.433  1.0
  O  O10  1  0.253  0.288  0.618  1.0
  O  O11  1  0.151  0.646  0.921  1.0
  O  O12  1  0.252  0.197  0.088  1.0
[/CIF]
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The material described by MgTb2V2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with two equivalent V(1)O4 tetrahedra and edges with two equivalent V(1)O4 tetrahedra. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. V(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 56°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Tb(1), and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Tb(1) and one V(1) atom. In the third O site, O(3) is bonded to one Mg(1), two equivalent Tb(1), and one V(1) atom to form distorted corner-sharing OTb2MgV trigonal pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Tb(1), and one V(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb2MgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.056
_cell_length_b   6.218
_cell_length_c   6.056
_cell_angle_alpha   105.508
_cell_angle_beta   105.910
_cell_angle_gamma   116.079
_symmetry_Int_Tables_number   1
_cell_volume   175.997
_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
  Tb  Tb0  1  0.153  0.912  0.296  1.0
  Tb  Tb1  1  0.884  0.088  0.741  1.0
  Mg  Mg2  1  0.736  0.500  0.736  1.0
  V  V3  1  0.356  0.646  0.758  1.0
  V  V4  1  0.612  0.354  0.210  1.0
  O  O5  1  0.830  0.712  0.465  1.0
  O  O6  1  0.391  0.803  0.555  1.0
  O  O7  1  0.738  0.805  0.946  1.0
  O  O8  1  0.775  0.354  0.005  1.0
  O  O9  1  0.641  0.195  0.433  1.0
  O  O10  1  0.253  0.288  0.618  1.0
  O  O11  1  0.151  0.646  0.921  1.0
  O  O12  1  0.252  0.197  0.088  1.0
[/CIF]
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