Materials Data on NaLiSi2H4O7 by Materials Project

Abstract

NaLiSi2H4O7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent LiO4 tetrahedra, corners with two equivalent SiO4 tetrahedra, edges with two equivalent NaO6 octahedra, and an edgeedge with one LiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.34–2.60 Å. Li1+ is bonded to four equivalent O2- atoms to form LiO4 tetrahedra that share corners with two equivalent NaO6 octahedra, corners with four equivalent SiO4 tetrahedra, an edgeedge with one NaO6 octahedra, and edges with two equivalent LiO4 tetrahedra. The corner-sharing octahedral tilt angles are 62°. There are two shorter (2.01 Å) and two longer (2.03 Å) Li–O bond lengths. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NaO6 octahedra, corners with two equivalent LiO4 tetrahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second 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 4-coordinate geometry to one Na1+, two equivalent Li1+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a linear geometry to two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms.