Materials Data on Ba2Ti(SiO4)2 by Materials Project

Abstract

Ba2TiSi2O8 crystallizes in the tetragonal P4bm space group. The structure is three-dimensional. Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.70–3.41 Å. Ti4+ is bonded to five O2- atoms to form distorted TiO5 trigonal bipyramids that share corners with four equivalent SiO4 tetrahedra. There is one shorter (1.70 Å) and four longer (1.99 Å) Ti–O bond length. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two equivalent TiO5 trigonal bipyramids. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to four equivalent Ba2+ and one Ti4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Ti4+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two equivalent Si4+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ba2+ and one Si4+ atom.