Materials Data on NaAlS2O19 by Materials Project
NaAlS2O17O2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional and consists of four oxygen molecules and one NaAlS2O17 framework. In the NaAlS2O17 framework, Na is bonded to six O atoms to form NaO6 octahedra that share corners with two equivalent NaO6 octahedra and corners with two equivalent SO4 tetrahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Na–O bond distances ranging from 2.33–2.57 Å. Al is bonded in a square co-planar geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.79–2.54 Å. S is bonded to four O atoms to form SO4 tetrahedra that share a cornercorner with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 51°. There is one shorter (1.48 Å) and three longer (1.49 Å) S–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Al atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Al and one O atom. The O–O bond length is 1.24 Å. In the third O site, O is bonded in a single-bond geometry to one Al atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to two equivalent Na atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Na and one O atom. In the sixth O site, O is bonded in a single-bond geometry to one S atom. In the seventh O site, O is bonded in a bent 120 degrees geometry to one Na and one S atom. In the eighth O site, O is bonded in a single-bond geometry to one S atom. In the ninth O site, O is bonded in a single-bond geometry to one S atom.