Hg2V2O7 crystallizes in the orthorhombic Pnma space group. The structure consists of four hydrogen peroxide molecules inside a V2Hg2O5 framework. In the V2Hg2O5 framework, there are two inequivalent V sites. In the first V site, V(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms. In the second V site, V(2) is bonded in a 4-coordinate geometry to one Hg(1), one O(6), and three equivalent O(2) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted single-bond geometry to one V(2) atom. In the second Hg site, Hg(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(3) and two equivalent O(5) atoms. There are five inequivalent O sites. In the first O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent V(2) atoms. In the second O site, O(3) is bonded to one V(1), two equivalent Hg(2), and one O(4) atom to form distorted corner-sharing OVHg2O tetrahedra. In the third O site, O(4) is bonded in a 2-coordinate geometry to one V(1) and one O(3) atom. In the fourth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent V(1) and two equivalent Hg(2) atoms. In the fifth O site, O(6) is bonded in a trigonal planar geometry to one V(2) and two equivalent V(1) atoms.
Hg2V2O7 crystallizes in the orthorhombic Pnma space group. The structure consists of four hydrogen peroxide molecules inside a V2Hg2O5 framework. In the V2Hg2O5 framework, there are two inequivalent V sites. In the first V site, V(1) is bonded in a 6-coordinate geometry to one O(3), one O(4), two equivalent O(5), and two equivalent O(6) atoms. The V(1)-O(3) bond length is 2.03 Å. The V(1)-O(4) bond length is 1.95 Å. Both V(1)-O(5) bond lengths are 2.21 Å. Both V(1)-O(6) bond lengths are 2.12 Å. In the second V site, V(2) is bonded in a 4-coordinate geometry to one Hg(1), one O(6), and three equivalent O(2) atoms. The V(2)-Hg(1) bond length is 2.94 Å. The V(2)-O(6) bond length is 1.85 Å. There are two shorter (1.89 Å) and one longer (2.06 Å) V(2)-O(2) bond length. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a distorted single-bond geometry to one V(2) atom. In the second Hg site, Hg(2) is bonded in a distorted rectangular see-saw-like geometry to two equivalent O(3) and two equivalent O(5) atoms. Both Hg(2)-O(3) bond lengths are 2.36 Å. Both Hg(2)-O(5) bond lengths are 2.33 Å. There are five inequivalent O sites. In the first O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent V(2) atoms. In the second O site, O(3) is bonded to one V(1), two equivalent Hg(2), and one O(4) atom to form distorted corner-sharing OVHg2O tetrahedra. The O(3)-O(4) bond length is 1.47 Å. In the third O site, O(4) is bonded in a 2-coordinate geometry to one V(1) and one O(3) atom. In the fourth O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent V(1) and two equivalent Hg(2) atoms. In the fifth O site, O(6) is bonded in a trigonal planar geometry to one V(2) and two equivalent V(1) atoms.