TlCHO2 crystallizes in the orthorhombic Pnna space group. Tl(1) is bonded in a distorted L-shaped geometry to four equivalent O(1) atoms. C(1) is bonded in a trigonal planar geometry to one H(1) and two equivalent O(1) atoms. H(1) is bonded in a single-bond geometry to one C(1) atom. O(1) is bonded in a distorted single-bond geometry to two equivalent Tl(1) and one C(1) atom.
TlCHO2 crystallizes in the orthorhombic Pnna space group. Tl(1) is bonded in a distorted L-shaped geometry to four equivalent O(1) atoms. There are two shorter (2.66 Å) and two longer (2.85 Å) Tl(1)-O(1) bond lengths. C(1) is bonded in a trigonal planar geometry to one H(1) and two equivalent O(1) atoms. The C(1)-H(1) bond length is 1.11 Å. Both C(1)-O(1) bond lengths are 1.27 Å. H(1) is bonded in a single-bond geometry to one C(1) atom. O(1) is bonded in a distorted single-bond geometry to two equivalent Tl(1) and one C(1) atom.