Materials Data on Na2SO4 by Materials Project

Na2SO4 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.37–2.87 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with six equivalent SO4 tetrahedra and edges with two equivalent NaO6 octahedra. There are two shorter (2.36 Å) and four longer (2.45 Å) Na–O bond lengths. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with six equivalent NaO6 octahedra. The corner-sharing octahedra tilt angles range from 41–49°. There is two shorter (1.48 Å) and two longer (1.50 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one S6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one S6+ atom.