Materials Data on Ta9V2O25 by Materials Project

Abstract

Ta9V2O25 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are three inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (1.98 Å) and four longer (2.02 Å) Ta–O bond lengths. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 1–30°. There are a spread of Ta–O bond distances ranging from 1.86–2.29 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share corners with four TaO6 octahedra, corners with two equivalent VO4 tetrahedra, and edges with two equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 6–29°. There are a spread of Ta–O bond distances ranging from 1.88–2.27 Å. V+2.50+ is bonded to four equivalent O2- atoms to form distorted VO4 tetrahedra that share corners with four equivalent TaO6 octahedra and edges with two equivalent VO4 tetrahedra. The corner-sharing octahedral tilt angles are 46°. All V–O bond lengths are 1.91 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ta5+ and two equivalent V+2.50+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. The O–Ta bond length is 1.86 Å. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. In the fifth O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. The O–Ta bond length is 1.86 Å. In the sixth O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to three Ta5+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to three Ta5+ atoms. In the ninth O2- site, O2- is bonded in a linear geometry to two Ta5+ atoms.