Materials Data on Ca2P2O7 by Materials Project
Ca2P2O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.71 Å. In the second Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.45 Å. 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 are a spread of P–O bond distances ranging from 1.52–1.62 Å. In the second 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 1.52–1.61 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+ and one P5+ atom.