The crystal structure described by MgV4(H4O7)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted VO5 trigonal bipyramids that share corners with four equivalent V(2)O4 tetrahedra and  an edgeedge with one V(1)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and corners with four equivalent V(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(6) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(6) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(7) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one V(1) and one V(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one V(2) and two equivalent V(1) atoms. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one V(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one V(1) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Mg(1) and one V(2) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Mg(1), one H(1), and one H(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(3), and one H(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgV4(H4O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.412
_cell_length_b   6.559
_cell_length_c   8.050
_cell_angle_alpha   86.666
_cell_angle_beta   66.119
_cell_angle_gamma   79.228
_symmetry_Int_Tables_number   1
_cell_volume   304.031
_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  0.500  1.0
  V  V1  1  0.126  0.840  0.101  1.0
  V  V2  1  0.874  0.160  0.899  1.0
  V  V3  1  0.308  0.320  0.970  1.0
  V  V4  1  0.692  0.680  0.030  1.0
  H  H5  1  0.546  0.790  0.712  1.0
  H  H6  1  0.454  0.210  0.288  1.0
  H  H7  1  0.685  0.853  0.509  1.0
  H  H8  1  0.315  0.147  0.491  1.0
  H  H9  1  0.968  0.421  0.324  1.0
  H  H10  1  0.032  0.579  0.676  1.0
  H  H11  1  0.906  0.257  0.487  1.0
  H  H12  1  0.094  0.743  0.513  1.0
  O  O13  1  0.141  0.533  0.112  1.0
  O  O14  1  0.859  0.467  0.888  1.0
  O  O15  1  0.876  0.871  0.011  1.0
  O  O16  1  0.124  0.129  0.989  1.0
  O  O17  1  0.464  0.788  0.965  1.0
  O  O18  1  0.536  0.212  0.035  1.0
  O  O19  1  0.029  0.895  0.320  1.0
  O  O20  1  0.971  0.105  0.680  1.0
  O  O21  1  0.420  0.392  0.755  1.0
  O  O22  1  0.580  0.608  0.245  1.0
  O  O23  1  0.560  0.781  0.586  1.0
  O  O24  1  0.440  0.219  0.414  1.0
  O  O25  1  0.842  0.369  0.425  1.0
  O  O26  1  0.158  0.631  0.575  1.0
[/CIF]
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The crystal structure described by MgV4(H4O7)2 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(5), two equivalent O(6), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted VO5 trigonal bipyramids that share corners with four equivalent V(2)O4 tetrahedra and  an edgeedge with one V(1)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra and corners with four equivalent V(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(6) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(6) atom. In the third H site, H(3) is bonded in a single-bond geometry to one O(7) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(7) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 150 degrees geometry to one V(1) and one V(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one V(2) and two equivalent V(1) atoms. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one V(1) and one V(2) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one V(1) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Mg(1) and one V(2) atom. In the sixth O site, O(6) is bonded in a distorted water-like geometry to one Mg(1), one H(1), and one H(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one H(3), and one H(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgV4(H4O7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.412
_cell_length_b   6.559
_cell_length_c   8.050
_cell_angle_alpha   86.666
_cell_angle_beta   66.119
_cell_angle_gamma   79.228
_symmetry_Int_Tables_number   1
_cell_volume   304.031
_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  0.500  1.0
  V  V1  1  0.126  0.840  0.101  1.0
  V  V2  1  0.874  0.160  0.899  1.0
  V  V3  1  0.308  0.320  0.970  1.0
  V  V4  1  0.692  0.680  0.030  1.0
  H  H5  1  0.546  0.790  0.712  1.0
  H  H6  1  0.454  0.210  0.288  1.0
  H  H7  1  0.685  0.853  0.509  1.0
  H  H8  1  0.315  0.147  0.491  1.0
  H  H9  1  0.968  0.421  0.324  1.0
  H  H10  1  0.032  0.579  0.676  1.0
  H  H11  1  0.906  0.257  0.487  1.0
  H  H12  1  0.094  0.743  0.513  1.0
  O  O13  1  0.141  0.533  0.112  1.0
  O  O14  1  0.859  0.467  0.888  1.0
  O  O15  1  0.876  0.871  0.011  1.0
  O  O16  1  0.124  0.129  0.989  1.0
  O  O17  1  0.464  0.788  0.965  1.0
  O  O18  1  0.536  0.212  0.035  1.0
  O  O19  1  0.029  0.895  0.320  1.0
  O  O20  1  0.971  0.105  0.680  1.0
  O  O21  1  0.420  0.392  0.755  1.0
  O  O22  1  0.580  0.608  0.245  1.0
  O  O23  1  0.560  0.781  0.586  1.0
  O  O24  1  0.440  0.219  0.414  1.0
  O  O25  1  0.842  0.369  0.425  1.0
  O  O26  1  0.158  0.631  0.575  1.0
[/CIF]
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