DOI: 10.17188/1262139
title: Materials Data on KNaP2H2O7 by Materials Project

description: KNaP2H2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.76–3.14 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.74–3.21 Å. There are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with five PO4 tetrahedra and an edgeedge with one NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.42–2.61 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with five PO4 tetrahedra and an edgeedge with one NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.41–2.58 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 NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–60°. 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 PO4 tetrahedra that share corners with three NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–59°. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–58°. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two NaO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–58°. There is two shorter (1.50 Å) and two longer (1.64 Å) P–O bond length. 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 0.98 Å. In the third 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 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 distorted bent 120 degrees geometry to one K1+ and two P5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two P5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two P5+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two P5+ atoms. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Na1+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two equivalent Na1+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, two equivalent Na1+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Na1+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one K1+, one Na1+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to two K1+, one Na1+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent K1+, one Na1+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one Na1+, and two H1+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one Na1+, and two H1+ atoms.