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DOE OSTI · 1350868

Materials Data on AlPO4 by Materials Project

Abstract

AlPO4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six PO4 tetrahedra and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.85–2.05 Å. In the second Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share corners with five PO4 tetrahedra and edges with two AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.77–1.96 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form distorted AlO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one AlO6 octahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.81–2.21 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 four AlO6 octahedra and corners with two equivalent AlO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 21–59°. There are a spread of P–O bond distances ranging from 1.50–1.60 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with five AlO6 octahedra and a cornercorner with one AlO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 35–53°. There are a spread of P–O bond distances ranging from 1.51–1.59 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three AlO6 octahedra and corners with two equivalent AlO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 16–56°. There are a spread of P–O bond distances ranging from 1.52–1.62 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ 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 linear geometry to one Al3+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Al3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Al3+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Al3+ and one P5+ atom.

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2020-07-15. Materials Data on AlPO4 by Materials Project. https://doi.org/10.17188/1350868

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