The compound described by Mg3(VO4)2 crystallizes in the trigonal R-3m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent V(1)O4 tetrahedra and edges with four equivalent Mg(1)O6 octahedra. V(1) is bonded to one O(2) and three equivalent O(1) atoms to form VO4 tetrahedra that share corners with nine equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. There are two inequivalent O sites. In the first O site, O(2) is bonded to three equivalent Mg(1) and one V(1) atom to form distorted corner-sharing OMg3V trigonal pyramids. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one V(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3V2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.739
_cell_length_b   5.739
_cell_length_c   5.739
_cell_angle_alpha   62.979
_cell_angle_beta   62.979
_cell_angle_gamma   62.979
_symmetry_Int_Tables_number   1
_cell_volume   142.471
_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  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.000  0.500  0.500  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  V  V3  1  0.876  0.876  0.876  1.0
  V  V4  1  0.124  0.124  0.124  1.0
  O  O5  1  0.237  0.772  0.237  1.0
  O  O6  1  0.744  0.744  0.744  1.0
  O  O7  1  0.763  0.763  0.228  1.0
  O  O8  1  0.228  0.763  0.763  1.0
  O  O9  1  0.237  0.237  0.772  1.0
  O  O10  1  0.772  0.237  0.237  1.0
  O  O11  1  0.763  0.228  0.763  1.0
  O  O12  1  0.256  0.256  0.256  1.0
[/CIF]
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The compound described by Mg3(VO4)2 crystallizes in the trigonal R-3m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent V(1)O4 tetrahedra and edges with four equivalent Mg(1)O6 octahedra. V(1) is bonded to one O(2) and three equivalent O(1) atoms to form VO4 tetrahedra that share corners with nine equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. There are two inequivalent O sites. In the first O site, O(2) is bonded to three equivalent Mg(1) and one V(1) atom to form distorted corner-sharing OMg3V trigonal pyramids. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Mg(1) and one V(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg3V2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.739
_cell_length_b   5.739
_cell_length_c   5.739
_cell_angle_alpha   62.979
_cell_angle_beta   62.979
_cell_angle_gamma   62.979
_symmetry_Int_Tables_number   1
_cell_volume   142.471
_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  0.500  0.500  0.000  1.0
  Mg  Mg1  1  0.000  0.500  0.500  1.0
  Mg  Mg2  1  0.500  0.000  0.500  1.0
  V  V3  1  0.876  0.876  0.876  1.0
  V  V4  1  0.124  0.124  0.124  1.0
  O  O5  1  0.237  0.772  0.237  1.0
  O  O6  1  0.744  0.744  0.744  1.0
  O  O7  1  0.763  0.763  0.228  1.0
  O  O8  1  0.228  0.763  0.763  1.0
  O  O9  1  0.237  0.237  0.772  1.0
  O  O10  1  0.772  0.237  0.237  1.0
  O  O11  1  0.763  0.228  0.763  1.0
  O  O12  1  0.256  0.256  0.256  1.0
[/CIF]
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