MgVAg3O4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted MgO4 tetrahedra that share corners with two equivalent V(1)O4 tetrahedra and  an edgeedge with one V(1)O4 tetrahedra. V(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted VO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and  an edgeedge with one Mg(1)O4 tetrahedra. There are two inequivalent Ag sites. In the first Ag site, Ag(1) is bonded in a linear geometry to two equivalent O(1) atoms. In the second Ag site, Ag(2) is bonded in a bent 120 degrees geometry to one O(2) and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one V(1), and two equivalent Ag(1) atoms to form a mixture of corner and edge-sharing OMgVAg2 tetrahedra. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one Ag(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one Ag(2) atom.
MgVAg3O4 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted MgO4 tetrahedra that share corners with two equivalent V(1)O4 tetrahedra and  an edgeedge with one V(1)O4 tetrahedra. The Mg(1)-O(2) bond length is 1.97 Å. The Mg(1)-O(3) bond length is 1.96 Å. Both Mg(1)-O(1) bond lengths are 2.01 Å. V(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted VO4 tetrahedra that share corners with two equivalent Mg(1)O4 tetrahedra and  an edgeedge with one Mg(1)O4 tetrahedra. The V(1)-O(2) bond length is 1.77 Å. The V(1)-O(3) bond length is 1.78 Å. Both V(1)-O(1) bond lengths are 1.92 Å. There are two inequivalent Ag sites. In the first Ag site, Ag(1) is bonded in a linear geometry to two equivalent O(1) atoms. There is one shorter (2.12 Å) and one longer (2.13 Å) Ag(1)-O(1) bond length. In the second Ag site, Ag(2) is bonded in a bent 120 degrees geometry to one O(2) and one O(3) atom. The Ag(2)-O(2) bond length is 2.44 Å. The Ag(2)-O(3) bond length is 2.51 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one V(1), and two equivalent Ag(1) atoms to form a mixture of corner and edge-sharing OMgVAg2 tetrahedra. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one Ag(2) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one Ag(2) atom.