Materials Data on KNaSO4 by Materials Project

Abstract

KNaSO4 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. K1+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of K–O bond distances ranging from 2.54–3.07 Å. There are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six equivalent O2- atoms to form NaO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Na–O bond lengths are 2.42 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Na–O bond lengths are 2.81 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 19°. There is one shorter (1.46 Å) and three longer (1.51 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent K1+, two Na1+, and one S6+ atom. In the second O2- site, O2- is bonded in a linear geometry to one K1+ and one S6+ atom.