DOE OSTI2020
V3(PO4)4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent V4+ sites. In the first V4+ site, V4+ is bonded to five O2- atoms to form VO5 trigonal bipyramids that share a cornercorner with one VO6 octahedra, corners with three PO4 tetrahedra, an edgeedge with one VO6 octahedra, and an edgeedge with one PO4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. There are a spread of V–O bond distances ranging from 1.80–1.97 Å. In the second V4+ site, V4+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one VO5 trigonal bipyramid. There are a spread of V–O bond distances ranging from 1.76–2.36 Å. In the third V4+ site, V4+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with six PO4 tetrahedra and a cornercorner with one VO5 trigonal bipyramid. There are a spread of V–O bond distances ranging from 1.88–2.48 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and corners with two equivalent VO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 33–53°. There are a spread of P–O bond distances ranging from 1.52–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and an edgeedge with one VO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 34–55°. There are a spread of P–O bond distances ranging from 1.46–1.64 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 18–39°. There is three shorter (1.53 Å) and one longer (1.61 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 43–48°. There are a spread of P–O bond distances ranging from 1.47–1.65 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two V4+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two V4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two V4+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a linear geometry to one V4+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a single-bond geometry to one P5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a bent 120 degrees geometry to one V4+ and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the sixteenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V4+ and one P5+ atom.