Materials Data on BaCrP2O7 by Materials Project
BaCrP2O7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.71–3.07 Å. Cr2+ is bonded to five O2- atoms to form distorted CrO5 square pyramids that share corners with five PO4 tetrahedra and an edgeedge with one CrO5 square pyramid. There are a spread of Cr–O bond distances ranging from 2.07–2.47 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent CrO5 square pyramids and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent CrO5 square pyramids and a cornercorner with one PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.63 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Cr2+, and one P5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ba2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to one Ba2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Cr2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Cr2+, and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, two equivalent Cr2+, and one P5+ atom.