Materials Data on Ba2TmCu3O7 by Materials Project
TmBa2Cu3O7 crystallizes in the orthorhombic Pmmm 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 2.75–3.04 Å. Tm3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.37 Å) and four longer (2.40 Å) Tm–O bond lengths. There are two inequivalent Cu+2.33+ sites. In the first Cu+2.33+ site, Cu+2.33+ is bonded to five O2- atoms to form corner-sharing CuO5 square pyramids. There are a spread of Cu–O bond distances ranging from 1.93–2.35 Å. In the second Cu+2.33+ site, Cu+2.33+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.95 Å) Cu–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Tm3+, and two equivalent Cu+2.33+ atoms. In the second O2- site, O2- is bonded to four equivalent Ba2+ and two Cu+2.33+ atoms to form a mixture of distorted corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Tm3+, and two equivalent Cu+2.33+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Cu+2.33+ atoms.