Materials Data on V7O4 by Materials Project
V7O4 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one V7O4 sheet oriented in the (0, 0, 1) direction. there are four inequivalent V sites. In the first V site, V is bonded in a 3-coordinate geometry to three O atoms. There are two shorter (2.23 Å) and one longer (2.24 Å) V–O bond lengths. In the second V site, V is bonded in a single-bond geometry to one O atom. The V–O bond length is 2.11 Å. In the third V site, V is bonded to five O atoms to form VO5 square pyramids that share corners with two equivalent VO6 octahedra, edges with three equivalent VO6 octahedra, and edges with four equivalent VO5 square pyramids. The corner-sharing octahedral tilt angles are 2°. There are a spread of V–O bond distances ranging from 2.21–2.27 Å. In the fourth V site, V is bonded to six O atoms to form VO6 octahedra that share corners with four equivalent VO5 square pyramids, edges with two equivalent VO6 octahedra, and edges with six equivalent VO5 square pyramids. There are two shorter (2.16 Å) and four longer (2.21 Å) V–O bond lengths. There are two inequivalent O sites. In the first O site, O is bonded to six V atoms to form a mixture of edge and corner-sharing OV6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the second O site, O is bonded to six V atoms to form a mixture of edge and corner-sharing OV6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°.