DOE OSTI2020
V3P4O17(NH4)2 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional and consists of eight ammonium molecules and one V3P4O17 framework. In the V3P4O17 framework, there are three inequivalent V4+ sites. In the first V4+ site, V4+ is bonded to five O2- atoms to form distorted VO5 trigonal bipyramids that share corners with four PO4 tetrahedra. There are a spread of V–O bond distances ranging from 1.64–2.00 Å. In the second V4+ site, V4+ is bonded in a 5-coordinate geometry to six O2- atoms. There are a spread of V–O bond distances ranging from 1.63–2.52 Å. In the third V4+ site, V4+ is bonded to six O2- atoms to form VO6 octahedra that share corners with two equivalent VO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedral tilt angles are 12°. There are a spread of V–O bond distances ranging from 1.69–2.04 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 a cornercorner with one VO6 octahedra, a cornercorner with one PO4 tetrahedra, and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 41°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO6 octahedra, a cornercorner with one PO4 tetrahedra, and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 35°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO6 octahedra, a cornercorner with one PO4 tetrahedra, and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 33°. There is three shorter (1.53 Å) and one longer (1.63 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one VO6 octahedra, a cornercorner with one PO4 tetrahedra, and a cornercorner with one VO5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 25°. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two V4+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V4+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V4+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one 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 single-bond geometry to one V4+ atom. In the tenth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted linear geometry to two equivalent V4+ atoms. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a bent 150 degrees geometry to one V4+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a bent 150 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. In the seventeenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one V4+ and one P5+ atom.