MgV2(SbO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with two equivalent V(2)O5 trigonal bipyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent Sb(1)O6 octahedra, 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(5), one O(6), one O(7), and one O(8) atom to form VO6 octahedra that share corners with three equivalent V(2)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. In the second V site, V(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(8) atom to form distorted VO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent V(1)O6 octahedra, corners with three equivalent Sb(1)O6 octahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form SbO6 octahedra that share corners with three equivalent V(2)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. In the second Sb site, Sb(2) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one V(2), one Sb(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one V(1), and one Sb(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one V(1), one Sb(1), and one Sb(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one V(2), one Sb(1), and one Sb(2) atom to form a mixture of distorted corner and edge-sharing OMgVSb2 trigonal pyramids. In the fifth O site, O(5) is bonded to one Mg(1), one V(1), one V(2), and one Sb(2) atom to form distorted OMgV2Sb trigonal pyramids that share corners with two equivalent O(8)MgV2Sb trigonal pyramids, corners with three equivalent O(4)MgVSb2 trigonal pyramids, and  an edgeedge with one O(8)MgV2Sb trigonal pyramid. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one V(1), one V(2), and one Sb(1) atom. In the seventh O site, O(7) is bonded in a trigonal non-coplanar geometry to one Mg(1), one V(1), and one Sb(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one V(1), one V(2), and one Sb(2) atom to form OMgV2Sb trigonal pyramids that share  a cornercorner with one O(4)MgVSb2 trigonal pyramid, corners with two equivalent O(5)MgV2Sb trigonal pyramids,  an edgeedge with one O(5)MgV2Sb trigonal pyramid, and  an edgeedge with one O(4)MgVSb2 trigonal pyramid.
MgV2(SbO4)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with two equivalent V(2)O5 trigonal bipyramids, edges with two equivalent V(1)O6 octahedra, edges with two equivalent Sb(1)O6 octahedra, and  an edgeedge with one V(2)O5 trigonal bipyramid. The Mg(1)-O(1) bond length is 2.17 Å. The Mg(1)-O(2) bond length is 2.02 Å. The Mg(1)-O(4) bond length is 2.12 Å. The Mg(1)-O(5) bond length is 2.20 Å. The Mg(1)-O(7) bond length is 2.02 Å. The Mg(1)-O(8) bond length is 2.13 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form VO6 octahedra that share corners with three equivalent V(2)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. The V(1)-O(2) bond length is 2.01 Å. The V(1)-O(3) bond length is 2.13 Å. The V(1)-O(5) bond length is 2.04 Å. The V(1)-O(6) bond length is 2.17 Å. The V(1)-O(7) bond length is 2.02 Å. The V(1)-O(8) bond length is 2.12 Å. In the second V site, V(2) is bonded to one O(1), one O(4), one O(5), one O(6), and one O(8) atom to form distorted VO5 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent V(1)O6 octahedra, corners with three equivalent Sb(1)O6 octahedra, and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. The V(2)-O(1) bond length is 2.03 Å. The V(2)-O(4) bond length is 2.17 Å. The V(2)-O(5) bond length is 2.05 Å. The V(2)-O(6) bond length is 1.94 Å. The V(2)-O(8) bond length is 2.09 Å. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form SbO6 octahedra that share corners with three equivalent V(2)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent V(1)O6 octahedra. The Sb(1)-O(1) bond length is 2.05 Å. The Sb(1)-O(2) bond length is 2.00 Å. The Sb(1)-O(3) bond length is 2.04 Å. The Sb(1)-O(4) bond length is 2.05 Å. The Sb(1)-O(6) bond length is 2.07 Å. The Sb(1)-O(7) bond length is 2.00 Å. In the second Sb site, Sb(2) is bonded in a 5-coordinate geometry to one O(1), one O(3), one O(4), one O(5), and one O(8) atom. The Sb(2)-O(1) bond length is 2.53 Å. The Sb(2)-O(3) bond length is 2.06 Å. The Sb(2)-O(4) bond length is 2.30 Å. The Sb(2)-O(5) bond length is 2.26 Å. The Sb(2)-O(8) bond length is 2.10 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one V(2), one Sb(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one V(1), and one Sb(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one V(1), one Sb(1), and one Sb(2) atom. In the fourth O site, O(4) is bonded to one Mg(1), one V(2), one Sb(1), and one Sb(2) atom to form a mixture of distorted corner and edge-sharing OMgVSb2 trigonal pyramids. In the fifth O site, O(5) is bonded to one Mg(1), one V(1), one V(2), and one Sb(2) atom to form distorted OMgV2Sb trigonal pyramids that share corners with two equivalent O(8)MgV2Sb trigonal pyramids, corners with three equivalent O(4)MgVSb2 trigonal pyramids, and  an edgeedge with one O(8)MgV2Sb trigonal pyramid. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one V(1), one V(2), and one Sb(1) atom. In the seventh O site, O(7) is bonded in a trigonal non-coplanar geometry to one Mg(1), one V(1), and one Sb(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one V(1), one V(2), and one Sb(2) atom to form OMgV2Sb trigonal pyramids that share  a cornercorner with one O(4)MgVSb2 trigonal pyramid, corners with two equivalent O(5)MgV2Sb trigonal pyramids,  an edgeedge with one O(5)MgV2Sb trigonal pyramid, and  an edgeedge with one O(4)MgVSb2 trigonal pyramid.