Materials Data on Sr2Ti(SiO4)2 by Materials Project
Sr2TiSi2O8 crystallizes in the tetragonal P4bm space group. The structure is three-dimensional. Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sr–O bond distances ranging from 2.63–2.91 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 (1.71 Å) and four longer (1.97 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 1.60–1.68 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Sr2+ and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, one Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Ti4+ atom.