The deformability of the thiophene ring: A key to the understanding of the conformational properties of oligo‐ and polythiophenes

Oligothiophenes in solution and in the solid state have different conformational properties, as can be concluded from the spectroscopic and theoretical data and X‐ray structure of three di‐ and tetramethyl α‐conjugated quaterthiophenes (see Figure) reported here. magnified image