Materials Data on Ba4Sc2Cu2O9 by Materials Project
Ba4Sc2Cu2O9 crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.74–3.03 Å. Sc3+ is bonded to six O2- atoms to form corner-sharing ScO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Sc–O bond distances ranging from 2.08–2.22 Å. Cu2+ is bonded in a T-shaped geometry to three O2- atoms. There is two shorter (1.82 Å) and one longer (1.91 Å) Cu–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent Ba2+, one Sc3+, and one Cu2+ atom. In the second O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Sc3+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Sc2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Sc3+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Sc2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Cu2+ atoms.