The crystal structure described by Mg3(VO4)2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Mg sites. In the first Mg site, 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(2)O6 octahedra. In the second Mg site, Mg(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent V(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Mg(2)O6 octahedra. V(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with six equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-57°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one V(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Mg(2), and one V(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(2) 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   6.477
_cell_length_b   6.477
_cell_length_c   8.293
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.452
_symmetry_Int_Tables_number   1
_cell_volume   286.859
_cell_formula_units_Z   2
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  0.000  0.500  1.0
  Mg  Mg2  1  0.114  0.386  0.750  1.0
  Mg  Mg3  1  0.386  0.114  0.250  1.0
  Mg  Mg4  1  0.614  0.886  0.750  1.0
  Mg  Mg5  1  0.886  0.614  0.250  1.0
  V  V6  1  0.120  0.880  0.880  1.0
  V  V7  1  0.880  0.120  0.120  1.0
  V  V8  1  0.380  0.620  0.380  1.0
  V  V9  1  0.620  0.380  0.620  1.0
  O  O10  1  0.848  0.612  0.500  1.0
  O  O11  1  0.612  0.848  0.500  1.0
  O  O12  1  0.652  0.888  0.000  1.0
  O  O13  1  0.888  0.652  1.000  1.0
  O  O14  1  0.152  0.388  0.500  1.0
  O  O15  1  0.388  0.152  0.500  1.0
  O  O16  1  0.348  0.112  1.000  1.0
  O  O17  1  0.112  0.348  0.000  1.0
  O  O18  1  0.997  0.003  0.746  1.0
  O  O19  1  0.003  0.997  0.254  1.0
  O  O20  1  0.248  0.752  0.773  1.0
  O  O21  1  0.752  0.248  0.227  1.0
  O  O22  1  0.252  0.748  0.273  1.0
  O  O23  1  0.748  0.252  0.727  1.0
  O  O24  1  0.497  0.503  0.754  1.0
  O  O25  1  0.503  0.497  0.246  1.0
[/CIF]
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The crystal structure described by Mg3(VO4)2 crystallizes in the orthorhombic Cmce space group. There are two inequivalent Mg sites. In the first Mg site, 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(2)O6 octahedra. In the second Mg site, Mg(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with six equivalent V(1)O4 tetrahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Mg(2)O6 octahedra. V(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form VO4 tetrahedra that share corners with three equivalent Mg(1)O6 octahedra and corners with six equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-57°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mg(2), and one V(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Mg(2), and one V(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Mg(2) 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   6.477
_cell_length_b   6.477
_cell_length_c   8.293
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   124.452
_symmetry_Int_Tables_number   1
_cell_volume   286.859
_cell_formula_units_Z   2
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  0.000  0.500  1.0
  Mg  Mg2  1  0.114  0.386  0.750  1.0
  Mg  Mg3  1  0.386  0.114  0.250  1.0
  Mg  Mg4  1  0.614  0.886  0.750  1.0
  Mg  Mg5  1  0.886  0.614  0.250  1.0
  V  V6  1  0.120  0.880  0.880  1.0
  V  V7  1  0.880  0.120  0.120  1.0
  V  V8  1  0.380  0.620  0.380  1.0
  V  V9  1  0.620  0.380  0.620  1.0
  O  O10  1  0.848  0.612  0.500  1.0
  O  O11  1  0.612  0.848  0.500  1.0
  O  O12  1  0.652  0.888  0.000  1.0
  O  O13  1  0.888  0.652  1.000  1.0
  O  O14  1  0.152  0.388  0.500  1.0
  O  O15  1  0.388  0.152  0.500  1.0
  O  O16  1  0.348  0.112  1.000  1.0
  O  O17  1  0.112  0.348  0.000  1.0
  O  O18  1  0.997  0.003  0.746  1.0
  O  O19  1  0.003  0.997  0.254  1.0
  O  O20  1  0.248  0.752  0.773  1.0
  O  O21  1  0.752  0.248  0.227  1.0
  O  O22  1  0.252  0.748  0.273  1.0
  O  O23  1  0.748  0.252  0.727  1.0
  O  O24  1  0.497  0.503  0.754  1.0
  O  O25  1  0.503  0.497  0.246  1.0
[/CIF]
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