Materials Data on Ca3Be2Si3(HO6)2 by Materials Project

Abstract

Ca3Be2Si3(HO6)2 crystallizes in the tetragonal P4_2/n space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.74 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.52 Å. Be2+ is bonded to four O2- atoms to form BeO4 tetrahedra that share corners with three SiO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.63–1.68 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two equivalent BeO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent BeO4 tetrahedra and corners with two equivalent SiO4 tetrahedra. There is two shorter (1.64 Å) and two longer (1.66 Å) Si–O bond length. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two Si4+ atoms. In the second O2- site, O2- is bonded to two Ca2+, one Be2+, and one Si4+ atom to form distorted corner-sharing OCa2BeSi trigonal pyramids. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Be2+, and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+, one Be2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ca2+, one Be2+, and one Si4+ atom.