Materials Data on NaAsH4O5 by Materials Project

Abstract

NaAsH4O5 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with four equivalent AsO4 tetrahedra and edges with two equivalent NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.39–2.56 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent NaO6 octahedra. The corner-sharing octahedra tilt angles range from 37–52°. There are a spread of As–O bond distances ranging from 1.68–1.76 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.63 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one As5+, and one H1+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one As5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one As5+ and two equivalent H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.