Materials Data on K2P2H2O7 by Materials Project

Abstract

K2H2P2O7 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of two hydrogen molecules and one K2P2HO7 ribbon oriented in the (0, 1, 1) direction. In the K2P2HO7 ribbon, there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 4-coordinate geometry to one P5+ and three O2- atoms. The K–P bond length is 2.31 Å. There are a spread of K–O bond distances ranging from 2.36–2.60 Å. In the second K1+ site, K1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.43–2.59 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a distorted single-bond geometry to three O2- atoms. There are a spread of P–O bond distances ranging from 1.01–2.01 Å. In the second P5+ site, P5+ is bonded in a distorted single-bond geometry to one K1+ and two O2- atoms. There is one shorter (1.15 Å) and one longer (1.74 Å) P–O bond length. H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.73 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one K1+ and one O2- atom. The O–O bond length is 1.21 Å. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two K1+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent K1+ atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one P5+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one O2- atom.