Abstract
A single crystal X-ray analysis of the crystal structure of [TlMe21,10-phen]ClO4confirms the presence of a bent dimethylthallium group with a C-Tl-C angle of 168.3 (1.5)°. The thallium coordination is best described as a distorted pentagonal bipyramid with one equatorial position vacant. The equatorial bonds are predominantly electrostatic, and the perchlorate ions are bidentate giving rise to a polymeric structure in the crystal.