V4O7 crystallizes in the triclinic P-1 space group. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form distorted VO6 pentagonal pyramids that share  a cornercorner with one V(4)O6 octahedra, corners with two equivalent V(3)O4 tetrahedra,  an edgeedge with one V(4)O6 octahedra, and edges with two equivalent V(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 22°. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. In the third V site, V(3) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing VO4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-68°. In the fourth V site, V(4) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form VO6 octahedra that share  a cornercorner with one V(1)O6 pentagonal pyramid, corners with four equivalent V(3)O4 tetrahedra,  an edgeedge with one V(4)O6 octahedra, and  an edgeedge with one V(1)O6 pentagonal pyramid. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one V(4) atom. In the second O site, O(2) is bonded to one V(2), one V(3), and two equivalent V(4) atoms to form a mixture of distorted corner and edge-sharing OV4 tetrahedra. In the third O site, O(3) is bonded in a see-saw-like geometry to one V(2), one V(4), and two equivalent V(1) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one V(2), one V(3), and one V(4) atom. In the fifth O site, O(5) is bonded to one V(2), one V(3), and two equivalent V(1) atoms to form a mixture of distorted corner and edge-sharing OV4 tetrahedra. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one V(3), one V(4), and one O(7) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one V(1), one V(2), and one O(6) atom.
V4O7 crystallizes in the triclinic P-1 space group. There are four inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(7), two equivalent O(3), and two equivalent O(5) atoms to form distorted VO6 pentagonal pyramids that share  a cornercorner with one V(4)O6 octahedra, corners with two equivalent V(3)O4 tetrahedra,  an edgeedge with one V(4)O6 octahedra, and edges with two equivalent V(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 22°. The V(1)-O(1) bond length is 1.95 Å. The V(1)-O(7) bond length is 2.08 Å. There is one shorter (2.08 Å) and one longer (2.14 Å) V(1)-O(3) bond length. There is one shorter (2.08 Å) and one longer (2.17 Å) V(1)-O(5) bond length. In the second V site, V(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. The V(2)-O(1) bond length is 1.95 Å. The V(2)-O(2) bond length is 2.26 Å. The V(2)-O(3) bond length is 2.02 Å. The V(2)-O(4) bond length is 1.97 Å. The V(2)-O(5) bond length is 2.07 Å. The V(2)-O(7) bond length is 2.33 Å. In the third V site, V(3) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form corner-sharing VO4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-68°. The V(3)-O(2) bond length is 1.93 Å. The V(3)-O(4) bond length is 1.84 Å. The V(3)-O(5) bond length is 1.94 Å. The V(3)-O(6) bond length is 2.01 Å. In the fourth V site, V(4) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form VO6 octahedra that share  a cornercorner with one V(1)O6 pentagonal pyramid, corners with four equivalent V(3)O4 tetrahedra,  an edgeedge with one V(4)O6 octahedra, and  an edgeedge with one V(1)O6 pentagonal pyramid. The V(4)-O(1) bond length is 1.98 Å. The V(4)-O(3) bond length is 2.11 Å. The V(4)-O(4) bond length is 2.00 Å. The V(4)-O(6) bond length is 2.02 Å. There is one shorter (2.03 Å) and one longer (2.12 Å) V(4)-O(2) bond length. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(2), and one V(4) atom. In the second O site, O(2) is bonded to one V(2), one V(3), and two equivalent V(4) atoms to form a mixture of distorted corner and edge-sharing OV4 tetrahedra. In the third O site, O(3) is bonded in a see-saw-like geometry to one V(2), one V(4), and two equivalent V(1) atoms. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one V(2), one V(3), and one V(4) atom. In the fifth O site, O(5) is bonded to one V(2), one V(3), and two equivalent V(1) atoms to form a mixture of distorted corner and edge-sharing OV4 tetrahedra. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one V(3), one V(4), and one O(7) atom. The O(6)-O(7) bond length is 1.51 Å. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one V(1), one V(2), and one O(6) atom.