data_Mg3V
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.52
_cell_length_b   5.52
_cell_length_c   5.52
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg3V
_chemical_formula_sum   'Mg6 V2'
_cell_volume   168.14
_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  0.76  0.14  0.0  1.0
  Mg  Mg1  1  0.76  0.38  0.0  1.0
  Mg  Mg2  1  0.14  0.0  0.76  1.0
  Mg  Mg3  1  0.0  0.76  0.14  1.0
  Mg  Mg4  1  0.0  0.76  0.38  1.0
  Mg  Mg5  1  0.38  0.0  0.76  1.0
  V  V6  1  0.76  0.76  0.76  1.0
  V  V7  1  0.0  0.0  0.0  1.0

data_Mg3V
_symmetry_space_group_name_H-M   R3
_cell_length_a   7.81
_cell_length_b   7.81
_cell_length_c   9.56
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   Mg3V
_chemical_formula_sum   'Mg18 V6'
_cell_volume   504.41
_cell_formula_units_Z   6
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+1/3, z+1/3'
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  9  -0.0  0.62  0.38  1.0
  Mg  Mg1  9  0.03  0.83  0.97  1.0
  V  V2  3  0.0  0.0  0.0  1.0
  V  V3  3  0.0  0.0  0.76  1.0

Mg Mg Mg Mg Mg Mg V V
Mg Mg Mg Mg Mg Mg V V 0 7 + o o 0 1 o o o 0 6 o - - 1 6 o o - 2 7 o o + 2 5 o o o 2 6 - - o 3 7 o + o 3 4 o o o 3 6 - o - 4 6 - o o 5 6 o - o 6 7 + + + 
Mg3V crystallizes in the trigonal R3 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a distorted single-bond geometry to one Mg(2), one V(1), and one V(2) atom. The Mg(1)-Mg(2) bond length is 1.33 Å. The Mg(1)-V(1) bond length is 2.48 Å. The Mg(1)-V(2) bond length is 1.53 Å. In the second Mg site, Mg(2) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one V(1) atom. The Mg(2)-V(1) bond length is 2.48 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded in a 7-coordinate geometry to three equivalent Mg(1), three equivalent Mg(2), and one V(2) atom. The V(1)-V(2) bond length is 2.30 Å. In the second V site, V(2) is bonded in a distorted trigonal planar geometry to three equivalent Mg(1) and one V(1) atom.