Materials Data on Ba2La2TlCu2O9 by Materials Project

Ba2La2Cu2TlO9 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 2.70–2.97 Å. La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.36–2.77 Å. Cu+2.50+ is bonded in a 5-coordinate geometry to five O2- atoms. There are four shorter (1.92 Å) and one longer (2.35 Å) Cu–O bond lengths. Tl3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TlO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.13 Å) and four longer (2.71 Å) Tl–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+ and one Tl3+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to five equivalent La3+ and one Cu+2.50+ atom. In the third O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Tl3+ atoms to form a mixture of edge and corner-sharing OBa2Tl4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Cu+2.50+ atoms.