Materials Data on Ba2Tl2CuO6 by Materials Project
Tl2Ba2CuO6 is (La,Ba)CuO4-derived structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.75–3.08 Å. Cu2+ is bonded in a square co-planar geometry to six O2- atoms. There are four shorter (1.96 Å) and two longer (2.79 Å) Cu–O bond lengths. Tl3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are a spread of Tl–O bond distances ranging from 2.02–2.77 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+, one Cu2+, and one Tl3+ atom. In the second O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Cu2+ atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedra tilt angles range from 0–45°. In the third O2- site, O2- is bonded to one Ba2+ and five equivalent Tl3+ atoms to form distorted OBaTl5 octahedra that share corners with eight OBa4Cu2 octahedra and edges with eight equivalent OBaTl5 octahedra. The corner-sharing octahedra tilt angles range from 8–45°.