Materials Data on Tl2GaCu3Se4 by Materials Project
Cu3Tl2GaSe4 is alpha bismuth trifluoride-derived structured and crystallizes in the orthorhombic C222 space group. The structure is three-dimensional. there are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four equivalent Se2- atoms to form CuSe4 tetrahedra that share corners with four equivalent GaSe4 tetrahedra and edges with four CuSe4 tetrahedra. All Cu–Se bond lengths are 2.55 Å. In the second Cu1+ site, Cu1+ is bonded to four equivalent Se2- atoms to form CuSe4 tetrahedra that share corners with four equivalent CuSe4 tetrahedra, edges with two equivalent CuSe4 tetrahedra, and edges with two equivalent GaSe4 tetrahedra. All Cu–Se bond lengths are 2.52 Å. In the third Cu1+ site, Cu1+ is bonded to four equivalent Se2- atoms to form CuSe4 tetrahedra that share corners with four equivalent CuSe4 tetrahedra, edges with two equivalent CuSe4 tetrahedra, and edges with two equivalent GaSe4 tetrahedra. All Cu–Se bond lengths are 2.52 Å. Tl1+ is bonded in a body-centered cubic geometry to eight equivalent Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.42–3.47 Å. Ga3+ is bonded to four equivalent Se2- atoms to form GaSe4 tetrahedra that share corners with four equivalent CuSe4 tetrahedra and edges with four CuSe4 tetrahedra. All Ga–Se bond lengths are 2.50 Å. Se2- is bonded in a 8-coordinate geometry to three Cu1+, four equivalent Tl1+, and one Ga3+ atom.