La3Tl is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent La(1), four equivalent La(2), and four equivalent Tl(1) atoms to form distorted LaLa8Tl4 cuboctahedra that share corners with twelve equivalent La(1)La8Tl4 cuboctahedra, edges with eight equivalent La(1)La8Tl4 cuboctahedra, edges with eight equivalent Tl(1)La12 cuboctahedra, faces with four equivalent Tl(1)La12 cuboctahedra, and faces with ten equivalent La(1)La8Tl4 cuboctahedra. In the second La site, La(2) is bonded in a distorted square co-planar geometry to eight equivalent La(1) and four equivalent Tl(1) atoms. Tl(1) is bonded to four equivalent La(2) and eight equivalent La(1) atoms to form TlLa12 cuboctahedra that share corners with four equivalent Tl(1)La12 cuboctahedra, edges with eight equivalent Tl(1)La12 cuboctahedra, edges with sixteen equivalent La(1)La8Tl4 cuboctahedra, faces with four equivalent Tl(1)La12 cuboctahedra, and faces with eight equivalent La(1)La8Tl4 cuboctahedra.
La3Tl is Uranium Silicide-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to four equivalent La(1), four equivalent La(2), and four equivalent Tl(1) atoms to form distorted LaLa8Tl4 cuboctahedra that share corners with twelve equivalent La(1)La8Tl4 cuboctahedra, edges with eight equivalent La(1)La8Tl4 cuboctahedra, edges with eight equivalent Tl(1)La12 cuboctahedra, faces with four equivalent Tl(1)La12 cuboctahedra, and faces with ten equivalent La(1)La8Tl4 cuboctahedra. All La(1)-La(1) bond lengths are 3.52 Å. All La(1)-La(2) bond lengths are 3.62 Å. All La(1)-Tl(1) bond lengths are 3.62 Å. In the second La site, La(2) is bonded in a distorted square co-planar geometry to eight equivalent La(1) and four equivalent Tl(1) atoms. All La(2)-Tl(1) bond lengths are 3.52 Å. Tl(1) is bonded to four equivalent La(2) and eight equivalent La(1) atoms to form TlLa12 cuboctahedra that share corners with four equivalent Tl(1)La12 cuboctahedra, edges with eight equivalent Tl(1)La12 cuboctahedra, edges with sixteen equivalent La(1)La8Tl4 cuboctahedra, faces with four equivalent Tl(1)La12 cuboctahedra, and faces with eight equivalent La(1)La8Tl4 cuboctahedra.