Materials Data on Ba2P2O7 by Materials Project
Ba2P2O7 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.85–3.14 Å. In the second Ba2+ site, Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.92–3.24 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.73–3.06 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.80 Å) and four longer (2.93 Å) Ba–O bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is three shorter (1.53 Å) and one 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 three shorter (1.54 Å) and one longer (1.61 Å) P–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two equivalent P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ba2+ and two equivalent P5+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one P5+ atom.