DOI: 10.17188/1287367
title: Materials Data on K2P2H2O7 by Materials Project

description: K2H2P2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.80–2.94 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of K–O bond distances ranging from 2.71–2.92 Å. In the third K1+ site, K1+ is bonded in a 9-coordinate geometry to one H1+ and eight O2- atoms. The K–H bond length is 2.80 Å. There are a spread of K–O bond distances ranging from 2.77–3.40 Å. In the fourth K1+ site, K1+ is bonded in a 6-coordinate geometry to one H1+ and five O2- atoms. The K–H bond length is 2.68 Å. There are a spread of K–O bond distances ranging from 2.61–3.00 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.64 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.49 Å) and two longer (1.65 Å) P–O bond length. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.66 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to two K1+ and one O2- atom. The H–O bond length is 0.97 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two K1+ and two P5+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one K1+ and two P5+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. 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 distorted single-bond geometry to two K1+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two K1+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to two K1+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a water-like geometry to two K1+ and two H1+ atoms. In the fourteenth O2- site, O2- is bonded in a water-like geometry to one K1+ and two H1+ atoms.