Materials Data on Ca2Al3H3O8 by Materials Project

Abstract

Ca2Al3H3O8 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six AlO4 tetrahedra and an edgeedge with one CaO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.32–2.47 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.53 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 two equivalent CaO6 octahedra and corners with three AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 61–65°. There are a spread of Al–O bond distances ranging from 1.76–1.82 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent CaO6 octahedra and corners with four equivalent AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. There is two shorter (1.77 Å) and two longer (1.79 Å) Al–O bond length. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+ and two Al3+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to one Ca2+ and two Al3+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+, one Al3+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to one Ca2+ and two equivalent Al3+ atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Ca2+ and one H1+ atom.