Materials Data on VP2H8(NO4)2 by Materials Project
(NH4)2VOP2O7 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of four ammonium molecules and one V(PO4)2 sheet oriented in the (1, 0, 0) direction. In the V(PO4)2 sheet, V4+ is bonded in a 5-coordinate geometry to five O2- atoms. There is one shorter (1.64 Å) and four longer (2.01 Å) V–O bond length. P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.65 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. The O–V bond length is 2.01 Å. The O–P bond length is 1.55 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one V4+ atom. The O–V bond length is 1.64 Å. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent P5+ atoms. Both O–P bond lengths are 1.65 Å. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. The O–V bond length is 2.01 Å. The O–P bond length is 1.55 Å. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. The O–P bond length is 1.55 Å. In the sixth O2- site, O2- is bonded in a single-bond geometry to one V4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent P5+ atoms. In the eighth O2- site, O2- is bonded in a distorted 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 P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. The O–P bond length is 1.55 Å. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one V4+ and one P5+ atom. The O–V bond length is 2.01 Å.