Materials Data on Na2W2O5 by Materials Project

Abstract

Na2W2O5 crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. Na1+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.97 Å. There are two inequivalent W4+ sites. In the first W4+ site, W4+ is bonded to six O2- atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are four shorter (2.05 Å) and two longer (2.15 Å) W–O bond lengths. In the second W4+ site, W4+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.89 Å) and two longer (2.00 Å) W–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to four equivalent Na1+ and two equivalent W4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Na1+ and two W4+ atoms. In the third O2- site, O2- is bonded to two equivalent Na1+ and two equivalent W4+ atoms to form corner-sharing ONa2W2 trigonal pyramids.