Materials Data on KSr4Si8H17O29 by Materials Project
KSr4Si8H17O29 crystallizes in the tetragonal P4nc space group. The structure is three-dimensional. K1+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (3.00 Å) and four longer (3.01 Å) K–O bond lengths. Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.55–2.67 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.65 Å. There are five 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 (1.64 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 0.97 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fourth 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 fifth H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.66 Å) H–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one K1+, one Sr2+, and two H1+ atoms. In the second O2- site, O2- is bonded to two equivalent Sr2+, one Si4+, and one H1+ atom to form a mixture of distorted edge and corner-sharing OSr2SiH tetrahedra. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded to two equivalent Sr2+, one Si4+, and one H1+ atom to form a mixture of distorted edge and corner-sharing OSr2SiH tetrahedra. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Si4+ atoms. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Si4+ atoms. In the seventh O2- site, O2- is bonded in a single-bond geometry to four equivalent Sr2+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to one K1+, one Sr2+, and two H1+ atoms.