The compound described by MgV2O5 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. V(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), and three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and two equivalent V(1) atoms to form OMg2V2 tetrahedra that share corners with two equivalent O(1)Mg2V2 tetrahedra, corners with two equivalent O(2)MgV3 trigonal pyramids, and edges with four equivalent O(2)MgV3 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1) and three equivalent V(1) atoms to form distorted OMgV3 trigonal pyramids that share  a cornercorner with one O(1)Mg2V2 tetrahedra, corners with three equivalent O(2)MgV3 trigonal pyramids, edges with two equivalent O(1)Mg2V2 tetrahedra, and edges with two equivalent O(2)MgV3 trigonal pyramids. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one V(1) atom. is represented by the CIF card [CIF]
data_MgV2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.427
_cell_length_b   5.427
_cell_length_c   11.210
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.861
_symmetry_Int_Tables_number   1
_cell_volume   212.862
_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  0.109  0.891  0.750  1.0
  Mg  Mg1  1  0.891  0.109  0.250  1.0
  V  V2  1  0.799  0.201  0.598  1.0
  V  V3  1  0.201  0.799  0.402  1.0
  V  V4  1  0.201  0.799  0.098  1.0
  V  V5  1  0.799  0.201  0.902  1.0
  O  O6  1  0.304  0.696  0.250  1.0
  O  O7  1  0.696  0.304  0.750  1.0
  O  O8  1  0.764  0.236  0.077  1.0
  O  O9  1  0.236  0.764  0.923  1.0
  O  O10  1  0.236  0.764  0.577  1.0
  O  O11  1  0.764  0.236  0.423  1.0
  O  O12  1  0.959  0.041  0.628  1.0
  O  O13  1  0.041  0.959  0.372  1.0
  O  O14  1  0.959  0.041  0.872  1.0
  O  O15  1  0.041  0.959  0.128  1.0
[/CIF]
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The compound described by MgV2O5 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. V(1) is bonded in a 5-coordinate geometry to one O(1), one O(3), and three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1) and two equivalent V(1) atoms to form OMg2V2 tetrahedra that share corners with two equivalent O(1)Mg2V2 tetrahedra, corners with two equivalent O(2)MgV3 trigonal pyramids, and edges with four equivalent O(2)MgV3 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1) and three equivalent V(1) atoms to form distorted OMgV3 trigonal pyramids that share  a cornercorner with one O(1)Mg2V2 tetrahedra, corners with three equivalent O(2)MgV3 trigonal pyramids, edges with two equivalent O(1)Mg2V2 tetrahedra, and edges with two equivalent O(2)MgV3 trigonal pyramids. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mg(1) and one V(1) atom. is represented by the CIF card [CIF]
data_MgV2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.427
_cell_length_b   5.427
_cell_length_c   11.210
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   139.861
_symmetry_Int_Tables_number   1
_cell_volume   212.862
_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  0.109  0.891  0.750  1.0
  Mg  Mg1  1  0.891  0.109  0.250  1.0
  V  V2  1  0.799  0.201  0.598  1.0
  V  V3  1  0.201  0.799  0.402  1.0
  V  V4  1  0.201  0.799  0.098  1.0
  V  V5  1  0.799  0.201  0.902  1.0
  O  O6  1  0.304  0.696  0.250  1.0
  O  O7  1  0.696  0.304  0.750  1.0
  O  O8  1  0.764  0.236  0.077  1.0
  O  O9  1  0.236  0.764  0.923  1.0
  O  O10  1  0.236  0.764  0.577  1.0
  O  O11  1  0.764  0.236  0.423  1.0
  O  O12  1  0.959  0.041  0.628  1.0
  O  O13  1  0.041  0.959  0.372  1.0
  O  O14  1  0.959  0.041  0.872  1.0
  O  O15  1  0.041  0.959  0.128  1.0
[/CIF]
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