PtTl crystallizes in the hexagonal P6/mmm space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a hexagonal planar geometry to six equivalent Tl(1) atoms. In the second Pt site, Pt(2) is bonded to six equivalent Tl(1) atoms to form a mixture of distorted corner, edge, and face-sharing PtTl6 pentagonal pyramids. Tl(1) is bonded to two equivalent Pt(1) and four equivalent Pt(2) atoms to form a mixture of distorted corner, edge, and face-sharing TlPt6 octahedra. The corner-sharing octahedral tilt angles range from 0-60°.
PtTl crystallizes in the hexagonal P6/mmm space group. There are two inequivalent Pt sites. In the first Pt site, Pt(1) is bonded in a hexagonal planar geometry to six equivalent Tl(1) atoms. All Pt(1)-Tl(1) bond lengths are 3.38 Å. In the second Pt site, Pt(2) is bonded to six equivalent Tl(1) atoms to form a mixture of distorted corner, edge, and face-sharing PtTl6 pentagonal pyramids. All Pt(2)-Tl(1) bond lengths are 2.74 Å. Tl(1) is bonded to two equivalent Pt(1) and four equivalent Pt(2) atoms to form a mixture of distorted corner, edge, and face-sharing TlPt6 octahedra. The corner-sharing octahedral tilt angles range from 0-60°.