The material described by MgY2V2O7 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(5) atoms to form distorted MgO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  a faceface with one V(2)O5 trigonal bipyramid. Y(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(5) atoms to form distorted YO6 pentagonal pyramids that share corners with two equivalent Mg(1)O5 trigonal bipyramids, corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted VO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  a cornercorner with one V(2)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form VO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  a faceface with one Mg(1)O5 trigonal bipyramid. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Y(1), and one V(1) atom to form OY2MgV tetrahedra that share corners with two equivalent O(1)Y2MgV tetrahedra,  a cornercorner with one O(3)Y2V2 trigonal pyramid, corners with three equivalent O(2)Y2V2 trigonal pyramids,  an edgeedge with one O(1)Y2MgV tetrahedra, and  an edgeedge with one O(3)Y2V2 trigonal pyramid. In the second O site, O(2) is bonded to two equivalent Y(1), one V(1), and one V(2) atom to form OY2V2 trigonal pyramids that share corners with six equivalent O(1)Y2MgV tetrahedra and edges with two equivalent O(3)Y2V2 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Y(1), one V(1), and one V(2) atom to form OY2V2 trigonal pyramids that share corners with two equivalent O(1)Y2MgV tetrahedra, edges with two equivalent O(1)Y2MgV tetrahedra, and edges with two equivalent O(2)Y2V2 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Mg(1), two equivalent Y(1), and one V(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2MgV2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.925
_cell_length_b   5.925
_cell_length_c   5.508
_cell_angle_alpha   85.705
_cell_angle_beta   94.295
_cell_angle_gamma   68.830
_symmetry_Int_Tables_number   1
_cell_volume   178.689
_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
  Y  Y0  1  0.327  0.314  0.500  1.0
  Y  Y1  1  0.686  0.673  0.500  1.0
  Mg  Mg2  1  0.051  0.949  0.415  1.0
  V  V3  1  0.260  0.740  0.906  1.0
  V  V4  1  0.729  0.271  0.097  1.0
  O  O5  1  0.058  0.658  0.641  1.0
  O  O6  1  0.342  0.942  0.641  1.0
  O  O7  1  0.438  0.562  0.227  1.0
  O  O8  1  0.564  0.436  0.775  1.0
  O  O9  1  0.021  0.979  0.047  1.0
  O  O10  1  0.655  0.049  0.332  1.0
  O  O11  1  0.951  0.345  0.332  1.0
[/CIF]
.
The material described by MgY2V2O7 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(4), two equivalent O(1), and two equivalent O(5) atoms to form distorted MgO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  a faceface with one V(2)O5 trigonal bipyramid. Y(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(5) atoms to form distorted YO6 pentagonal pyramids that share corners with two equivalent Mg(1)O5 trigonal bipyramids, corners with two equivalent V(1)O5 trigonal bipyramids, corners with two equivalent V(2)O5 trigonal bipyramids, edges with three equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid,  an edgeedge with one V(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(4), and two equivalent O(1) atoms to form distorted VO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one Mg(1)O5 trigonal bipyramid,  a cornercorner with one V(2)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one V(2)O5 trigonal bipyramid. In the second V site, V(2) is bonded to one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form VO5 trigonal bipyramids that share corners with four equivalent Y(1)O6 pentagonal pyramids,  a cornercorner with one V(1)O5 trigonal bipyramid, edges with two equivalent Y(1)O6 pentagonal pyramids,  an edgeedge with one V(1)O5 trigonal bipyramid, and  a faceface with one Mg(1)O5 trigonal bipyramid. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Y(1), and one V(1) atom to form OY2MgV tetrahedra that share corners with two equivalent O(1)Y2MgV tetrahedra,  a cornercorner with one O(3)Y2V2 trigonal pyramid, corners with three equivalent O(2)Y2V2 trigonal pyramids,  an edgeedge with one O(1)Y2MgV tetrahedra, and  an edgeedge with one O(3)Y2V2 trigonal pyramid. In the second O site, O(2) is bonded to two equivalent Y(1), one V(1), and one V(2) atom to form OY2V2 trigonal pyramids that share corners with six equivalent O(1)Y2MgV tetrahedra and edges with two equivalent O(3)Y2V2 trigonal pyramids. In the third O site, O(3) is bonded to two equivalent Y(1), one V(1), and one V(2) atom to form OY2V2 trigonal pyramids that share corners with two equivalent O(1)Y2MgV tetrahedra, edges with two equivalent O(1)Y2MgV tetrahedra, and edges with two equivalent O(2)Y2V2 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(1), and one V(2) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Mg(1), two equivalent Y(1), and one V(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Y2MgV2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.925
_cell_length_b   5.925
_cell_length_c   5.508
_cell_angle_alpha   85.705
_cell_angle_beta   94.295
_cell_angle_gamma   68.830
_symmetry_Int_Tables_number   1
_cell_volume   178.689
_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
  Y  Y0  1  0.327  0.314  0.500  1.0
  Y  Y1  1  0.686  0.673  0.500  1.0
  Mg  Mg2  1  0.051  0.949  0.415  1.0
  V  V3  1  0.260  0.740  0.906  1.0
  V  V4  1  0.729  0.271  0.097  1.0
  O  O5  1  0.058  0.658  0.641  1.0
  O  O6  1  0.342  0.942  0.641  1.0
  O  O7  1  0.438  0.562  0.227  1.0
  O  O8  1  0.564  0.436  0.775  1.0
  O  O9  1  0.021  0.979  0.047  1.0
  O  O10  1  0.655  0.049  0.332  1.0
  O  O11  1  0.951  0.345  0.332  1.0
[/CIF]
.