DOI: 10.17188/1261833
title: Materials Data on Na2SiH16O11 by Materials Project

description: Na2Si(H7O5)2H2O crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four water molecules and one Na2Si(H7O5)2 sheet oriented in the (1, 0, 0) direction. In the Na2Si(H7O5)2 sheet, there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.57 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form edge-sharing NaO6 octahedra. There are a spread of Na–O bond distances ranging from 2.39–2.53 Å. Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Si–O bond distances ranging from 1.62–1.72 Å. There are fourteen 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 1.00 Å. In the second H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.04 Å) and one longer (1.58 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the fourth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.60 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. In the sixth 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 seventh 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 eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the ninth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.60 Å) H–O bond length. In the tenth 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 eleventh 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 twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the thirteenth 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 fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Si4+ and three H1+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Si4+ and one H1+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Si4+, and one H1+ atom. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to two equivalent Na1+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and three H1+ atoms. In the ninth O2- site, O2- is bonded in a distorted water-like geometry to two Na1+ and two H1+ atoms. In the tenth O2- site, O2- is bonded in a water-like geometry to one Na1+ and two H1+ atoms.