The crystal structure described by MgNb2V2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  an edgeedge with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-65°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Nb site, Nb(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with two equivalent V(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent V(1)O6 octahedra, and edges with two equivalent V(2)O6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are two inequivalent V sites. In the first V site, V(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form VO6 octahedra that share edges with two equivalent Nb(2)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. In the second V site, V(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form VO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Nb(2)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Nb(1), one Nb(2), one V(1), and one V(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Nb(1), one Nb(2), one V(1), and one V(2) atom. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Nb(2), and one V(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Nb(1), and one V(1) atom. is represented by the CIF file [CIF]
data_MgNb2V2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.658
_cell_length_b   7.659
_cell_length_c   8.057
_cell_angle_alpha   142.994
_cell_angle_beta   142.155
_cell_angle_gamma   47.870
_symmetry_Int_Tables_number   1
_cell_volume   173.464
_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
  Mg  Mg0  1  0.234  0.984  0.250  1.0
  Nb  Nb1  1  0.905  0.655  0.250  1.0
  Nb  Nb2  1  0.076  0.326  0.750  1.0
  V  V3  1  0.431  0.181  0.250  1.0
  V  V4  1  0.564  0.814  0.750  1.0
  O  O5  1  0.722  0.471  0.782  1.0
  O  O6  1  0.790  0.051  0.274  1.0
  O  O7  1  0.358  0.140  0.676  1.0
  O  O8  1  0.069  0.326  0.244  1.0
  O  O9  1  0.964  0.682  0.824  1.0
  O  O10  1  0.582  0.825  0.256  1.0
  O  O11  1  0.190  0.941  0.718  1.0
  O  O12  1  0.277  0.516  0.226  1.0
[/CIF]
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The crystal structure described by MgNb2V2O8 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MgO4 tetrahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent V(2)O6 octahedra, and  an edgeedge with one V(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 61-65°. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Nb site, Nb(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NbO6 octahedra that share corners with two equivalent V(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent V(1)O6 octahedra, and edges with two equivalent V(2)O6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are two inequivalent V sites. In the first V site, V(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form VO6 octahedra that share edges with two equivalent Nb(2)O6 octahedra, edges with two equivalent V(2)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. In the second V site, V(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form VO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, edges with two equivalent Nb(2)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. The corner-sharing octahedral tilt angles are 29°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Nb(1), one Nb(2), one V(1), and one V(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Nb(1), one Nb(2), one V(1), and one V(2) atom. In the third O site, O(3) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Nb(2), and one V(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Nb(1), and one V(1) atom. is represented by the CIF file [CIF]
data_MgNb2V2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.658
_cell_length_b   7.659
_cell_length_c   8.057
_cell_angle_alpha   142.994
_cell_angle_beta   142.155
_cell_angle_gamma   47.870
_symmetry_Int_Tables_number   1
_cell_volume   173.464
_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
  Mg  Mg0  1  0.234  0.984  0.250  1.0
  Nb  Nb1  1  0.905  0.655  0.250  1.0
  Nb  Nb2  1  0.076  0.326  0.750  1.0
  V  V3  1  0.431  0.181  0.250  1.0
  V  V4  1  0.564  0.814  0.750  1.0
  O  O5  1  0.722  0.471  0.782  1.0
  O  O6  1  0.790  0.051  0.274  1.0
  O  O7  1  0.358  0.140  0.676  1.0
  O  O8  1  0.069  0.326  0.244  1.0
  O  O9  1  0.964  0.682  0.824  1.0
  O  O10  1  0.582  0.825  0.256  1.0
  O  O11  1  0.190  0.941  0.718  1.0
  O  O12  1  0.277  0.516  0.226  1.0
[/CIF]
.