Materials Data on Cs2Al2P2O9 by Materials Project
Cs2Al2P2O9 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one Cs2Al2P2O9 sheet oriented in the (0, 0, 1) direction. Cs1+ is bonded in a 2-coordinate geometry to two equivalent O2- atoms. There are one shorter (3.03 Å) and one longer (3.15 Å) Cs–O bond lengths. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three equivalent PO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.71–1.79 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent AlO4 tetrahedra. There is one shorter (1.50 Å) and three longer (1.57 Å) P–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Cs1+ and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Al3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to two equivalent Al3+ atoms.