The compound described by Ba3MgV2O8 crystallizes in the trigonal R-3m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(1) and nine equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with six equivalent Ba(2)O12 cuboctahedra, and edges with six equivalent V(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 9°. Mg(1) is bonded to six equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with six equivalent Ba(2)O12 cuboctahedra and faces with two equivalent V(1)O4 trigonal pyramids. V(1) is bonded to one O(1) and three equivalent O(2) atoms to form distorted VO4 trigonal pyramids that share edges with three equivalent Ba(2)O12 cuboctahedra and  a faceface with one Mg(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), and one V(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Mg(1), and one V(1) atom. is represented by the CIF file [CIF]
data_Ba3MgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.312
_cell_length_b   8.312
_cell_length_c   8.312
_cell_angle_alpha   41.668
_cell_angle_beta   41.668
_cell_angle_gamma   41.668
_symmetry_Int_Tables_number   1
_cell_volume   229.472
_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
  Ba  Ba0  1  0.204  0.204  0.204  1.0
  Ba  Ba1  1  0.796  0.796  0.796  1.0
  Ba  Ba2  1  0.000  0.000  0.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  V  V4  1  0.607  0.607  0.607  1.0
  V  V5  1  0.393  0.393  0.393  1.0
  O  O6  1  0.684  0.684  0.684  1.0
  O  O7  1  0.316  0.316  0.316  1.0
  O  O8  1  0.256  0.717  0.717  1.0
  O  O9  1  0.717  0.717  0.256  1.0
  O  O10  1  0.717  0.256  0.717  1.0
  O  O11  1  0.744  0.283  0.283  1.0
  O  O12  1  0.283  0.744  0.283  1.0
  O  O13  1  0.283  0.283  0.744  1.0
[/CIF]
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The compound described by Ba3MgV2O8 crystallizes in the trigonal R-3m space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(1) and nine equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with six equivalent Ba(2)O12 cuboctahedra, and edges with six equivalent V(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 9°. Mg(1) is bonded to six equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with six equivalent Ba(2)O12 cuboctahedra and faces with two equivalent V(1)O4 trigonal pyramids. V(1) is bonded to one O(1) and three equivalent O(2) atoms to form distorted VO4 trigonal pyramids that share edges with three equivalent Ba(2)O12 cuboctahedra and  a faceface with one Mg(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), and one V(1) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(2), three equivalent Ba(1), one Mg(1), and one V(1) atom. is represented by the CIF file [CIF]
data_Ba3MgV2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.312
_cell_length_b   8.312
_cell_length_c   8.312
_cell_angle_alpha   41.668
_cell_angle_beta   41.668
_cell_angle_gamma   41.668
_symmetry_Int_Tables_number   1
_cell_volume   229.472
_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
  Ba  Ba0  1  0.204  0.204  0.204  1.0
  Ba  Ba1  1  0.796  0.796  0.796  1.0
  Ba  Ba2  1  0.000  0.000  0.000  1.0
  Mg  Mg3  1  0.500  0.500  0.500  1.0
  V  V4  1  0.607  0.607  0.607  1.0
  V  V5  1  0.393  0.393  0.393  1.0
  O  O6  1  0.684  0.684  0.684  1.0
  O  O7  1  0.316  0.316  0.316  1.0
  O  O8  1  0.256  0.717  0.717  1.0
  O  O9  1  0.717  0.717  0.256  1.0
  O  O10  1  0.717  0.256  0.717  1.0
  O  O11  1  0.744  0.283  0.283  1.0
  O  O12  1  0.283  0.744  0.283  1.0
  O  O13  1  0.283  0.283  0.744  1.0
[/CIF]
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