Materials Data on BaCu(SiO3)2 by Materials Project

Abstract

BaCuSi2O6 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. Ba2+ is bonded in a 6-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.71–3.30 Å. Cu2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.96 Å) and two longer (1.97 Å) Cu–O bond length. Si4+ is bonded to four O2- atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.63 Å) and two longer (1.66 Å) Si–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ba2+ and two equivalent Si4+ atoms.