Materials Data on K3Al2(PO4)3 by Materials Project
K3Al2(PO4)3 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.73–3.37 Å. In the second K1+ site, K1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of K–O bond distances ranging from 2.66–3.25 Å. In the third 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 2.68–3.27 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.77 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four PO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.77 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two AlO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three AlO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.57 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three AlO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.51–1.57 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one K1+, one Al3+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Al3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one K1+, one Al3+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Al3+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent K1+, one Al3+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to three K1+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+, one Al3+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one K1+, one Al3+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one K1+, one Al3+, and one P5+ atom.