Materials Data on BaCu(SiO3)2 by Materials Project

BaCuSi2O6 crystallizes in the tetragonal I4_1cd 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 2.72–3.33 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.96 Å) and two longer (1.98 Å) Cu–O bond length. In the second Cu2+ site, Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There is two shorter (1.95 Å) and two longer (1.97 Å) Cu–O bond length. 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 1.63–1.66 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 1.62–1.66 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ba2+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ba2+ and two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Cu2+, and one Si4+ atom.